diff --git a/tests/base.py b/tests/base.py
index 552bdd6..6092626 100755
--- a/tests/base.py
+++ b/tests/base.py
@@ -541,14 +541,21 @@
 class FakeBuild(object):
     log = logging.getLogger("zuul.test")
 
-    def __init__(self, launch_server, job, node):
+    def __init__(self, launch_server, job):
         self.daemon = True
         self.launch_server = launch_server
         self.job = job
         self.jobdir = None
         self.uuid = job.unique
-        self.node = node
         self.parameters = json.loads(job.arguments)
+        # TODOv3(jeblair): self.node is really "the image of the node
+        # assigned".  We should rename it (self.node_image?) if we
+        # keep using it like this, or we may end up exposing more of
+        # the complexity around multi-node jobs here
+        # (self.nodes[0].image?)
+        self.node = None
+        if len(self.parameters.get('nodes')) == 1:
+            self.node = self.parameters['nodes'][0]['image']
         self.unique = self.parameters['ZUUL_UUID']
         self.name = self.parameters['job']
         self.wait_condition = threading.Condition()
@@ -707,8 +714,7 @@
                        (regex, len(self.running_builds)))
 
     def launchJob(self, job):
-        node = None
-        build = FakeBuild(self, job, node)
+        build = FakeBuild(self, job)
         job.build = build
         self.running_builds.append(build)
         self.job_builds[job.unique] = build
@@ -1477,7 +1483,7 @@
                 self.log.error("No running builds")
             raise
 
-    def assertHistory(self, history):
+    def assertHistory(self, history, ordered=True):
         """Assert that the completed builds are as described.
 
         The list of completed builds is examined and must match
@@ -1488,14 +1494,37 @@
             history, and each element of the dictionary must match the
             corresponding attribute of the build.
 
+        :arg bool ordered: If true, the history must match the order
+            supplied, if false, the builds are permitted to have
+            arrived in any order.
+
         """
+        def matches(history_item, item):
+            for k, v in item.items():
+                if getattr(history_item, k) != v:
+                    return False
+            return True
         try:
             self.assertEqual(len(self.history), len(history))
-            for i, d in enumerate(history):
-                for k, v in d.items():
-                    self.assertEqual(
-                        getattr(self.history[i], k), v,
-                        "Element %i in history does not match" % (i,))
+            if ordered:
+                for i, d in enumerate(history):
+                    if not matches(self.history[i], d):
+                        raise Exception(
+                            "Element %i in history does not match" % (i,))
+            else:
+                unseen = self.history[:]
+                for i, d in enumerate(history):
+                    found = False
+                    for unseen_item in unseen:
+                        if matches(unseen_item, d):
+                            found = True
+                            unseen.remove(unseen_item)
+                            break
+                    if not found:
+                        raise Exception("No match found for element %i "
+                                        "in history" % (i,))
+                if unseen:
+                    raise Exception("Unexpected items in history")
         except Exception:
             for build in self.history:
                 self.log.error("Completed build: %s" % build)
diff --git a/tests/fixtures/config/multi-tenant/git/tenant-one-config/zuul.yaml b/tests/fixtures/config/multi-tenant/git/tenant-one-config/zuul.yaml
index 785f8a5..4a653f6 100644
--- a/tests/fixtures/config/multi-tenant/git/tenant-one-config/zuul.yaml
+++ b/tests/fixtures/config/multi-tenant/git/tenant-one-config/zuul.yaml
@@ -21,6 +21,12 @@
         verified: 0
     precedence: high
 
+- nodeset:
+    name: nodeset1
+    nodes:
+      - name: controller
+        image: controller-image
+
 - job:
     name:
       project1-test1
diff --git a/tests/fixtures/config/multi-tenant/git/tenant-two-config/zuul.yaml b/tests/fixtures/config/multi-tenant/git/tenant-two-config/zuul.yaml
index c6127ca..7c79720 100644
--- a/tests/fixtures/config/multi-tenant/git/tenant-two-config/zuul.yaml
+++ b/tests/fixtures/config/multi-tenant/git/tenant-two-config/zuul.yaml
@@ -21,6 +21,12 @@
         verified: 0
     precedence: high
 
+- nodeset:
+    name: nodeset1
+    nodes:
+      - name: controller
+        image: controller-image
+
 - job:
     name:
       project2-test1
diff --git a/tests/fixtures/config/openstack/git/openstack_keystone/README b/tests/fixtures/config/openstack/git/openstack_keystone/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/openstack/git/openstack_keystone/README
@@ -0,0 +1 @@
+test
diff --git a/tests/fixtures/config/openstack/git/openstack_nova/README b/tests/fixtures/config/openstack/git/openstack_nova/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/openstack/git/openstack_nova/README
@@ -0,0 +1 @@
+test
diff --git a/tests/fixtures/config/openstack/git/project-config/zuul.yaml b/tests/fixtures/config/openstack/git/project-config/zuul.yaml
new file mode 100644
index 0000000..9c2231a
--- /dev/null
+++ b/tests/fixtures/config/openstack/git/project-config/zuul.yaml
@@ -0,0 +1,88 @@
+# Pipeline definitions
+
+- pipeline:
+    name: check
+    manager: independent
+    success-message: Build succeeded (check).
+    source:
+      gerrit
+    trigger:
+      gerrit:
+        - event: patchset-created
+    success:
+      gerrit:
+        verified: 1
+    failure:
+      gerrit:
+        verified: -1
+
+- pipeline:
+    name: gate
+    manager: dependent
+    success-message: Build succeeded (gate).
+    source:
+      gerrit
+    trigger:
+      gerrit:
+        - event: comment-added
+          approval:
+            - approved: 1
+    success:
+      gerrit:
+        verified: 2
+        submit: true
+    failure:
+      gerrit:
+        verified: -2
+    start:
+      gerrit:
+        verified: 0
+    precedence: high
+
+# Job definitions
+
+- job:
+    name: base
+    timeout: 30
+    nodes:
+      - name: controller
+        image: ubuntu-xenial
+
+- job:
+    name: python27
+    parent: base
+
+- job:
+    name: python27
+    parent: base
+    branches: stable/mitaka
+    nodes:
+      - name: controller
+        image: ubuntu-trusty
+
+- job:
+    name: python35
+    parent: base
+
+- project-template:
+    name: python-jobs
+    gate:
+      jobs:
+        - python27
+        - python35
+
+# Project definitions
+
+- project:
+    name: openstack/nova
+    templates:
+      - python-jobs
+    gate:
+      queue: integrated
+
+- project:
+    name: openstack/keystone
+    templates:
+      - python-jobs
+    gate:
+      queue: integrated
diff --git a/tests/fixtures/config/openstack/main.yaml b/tests/fixtures/config/openstack/main.yaml
new file mode 100644
index 0000000..95a0952
--- /dev/null
+++ b/tests/fixtures/config/openstack/main.yaml
@@ -0,0 +1,6 @@
+- tenant:
+    name: openstack
+    source:
+      gerrit:
+        config-repos:
+          - project-config
diff --git a/tests/fixtures/config/single-tenant/git/common-config/zuul.yaml b/tests/fixtures/config/single-tenant/git/common-config/zuul.yaml
index 3a88863..01de2aa 100644
--- a/tests/fixtures/config/single-tenant/git/common-config/zuul.yaml
+++ b/tests/fixtures/config/single-tenant/git/common-config/zuul.yaml
@@ -42,6 +42,16 @@
 
 - job:
     name: project-test1
+    nodes:
+      - name: controller
+        image: image1
+
+- job:
+    name: project-test1
+    branches: stable
+    nodes:
+      - name: controller
+        image: image2
 
 - job:
     name: project-test2
@@ -54,3 +64,23 @@
             jobs:
               - project-test1
               - project-test2
+
+- project:
+    name: org/project1
+    gate:
+      queue: integrated
+      jobs:
+        - project-merge:
+            jobs:
+              - project-test1
+              - project-test2
+
+- project:
+    name: org/project2
+    gate:
+      queue: integrated
+      jobs:
+        - project-merge:
+            jobs:
+              - project-test1
+              - project-test2
diff --git a/tests/fixtures/config/single-tenant/git/org_project1/README b/tests/fixtures/config/single-tenant/git/org_project1/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/single-tenant/git/org_project1/README
@@ -0,0 +1 @@
+test
diff --git a/tests/fixtures/config/single-tenant/git/org_project2/README b/tests/fixtures/config/single-tenant/git/org_project2/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/single-tenant/git/org_project2/README
@@ -0,0 +1 @@
+test
diff --git a/tests/test_openstack.py b/tests/test_openstack.py
new file mode 100644
index 0000000..175b4bd
--- /dev/null
+++ b/tests/test_openstack.py
@@ -0,0 +1,62 @@
+#!/usr/bin/env python
+
+# Copyright 2012 Hewlett-Packard Development Company, L.P.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import logging
+
+from tests.base import AnsibleZuulTestCase
+
+logging.basicConfig(level=logging.DEBUG,
+                    format='%(asctime)s %(name)-32s '
+                    '%(levelname)-8s %(message)s')
+
+
+class TestOpenStack(AnsibleZuulTestCase):
+    # A temporary class to experiment with how openstack can use
+    # Zuulv3
+
+    tenant_config_file = 'config/openstack/main.yaml'
+
+    def test_nova_master(self):
+        A = self.fake_gerrit.addFakeChange('openstack/nova', 'master', 'A')
+        A.addApproval('code-review', 2)
+        self.fake_gerrit.addEvent(A.addApproval('approved', 1))
+        self.waitUntilSettled()
+        self.assertEqual(self.getJobFromHistory('python27').result,
+                         'SUCCESS')
+        self.assertEqual(self.getJobFromHistory('python35').result,
+                         'SUCCESS')
+        self.assertEqual(A.data['status'], 'MERGED')
+        self.assertEqual(A.reported, 2,
+                         "A should report start and success")
+        self.assertEqual(self.getJobFromHistory('python27').node,
+                         'ubuntu-xenial')
+
+    def test_nova_mitaka(self):
+        self.create_branch('openstack/nova', 'stable/mitaka')
+        A = self.fake_gerrit.addFakeChange('openstack/nova',
+                                           'stable/mitaka', 'A')
+        A.addApproval('code-review', 2)
+        self.fake_gerrit.addEvent(A.addApproval('approved', 1))
+        self.waitUntilSettled()
+        self.assertEqual(self.getJobFromHistory('python27').result,
+                         'SUCCESS')
+        self.assertEqual(self.getJobFromHistory('python35').result,
+                         'SUCCESS')
+        self.assertEqual(A.data['status'], 'MERGED')
+        self.assertEqual(A.reported, 2,
+                         "A should report start and success")
+        self.assertEqual(self.getJobFromHistory('python27').node,
+                         'ubuntu-trusty')
diff --git a/tests/test_scheduler.py b/tests/test_scheduler.py
index fe814e8..abb0548 100755
--- a/tests/test_scheduler.py
+++ b/tests/test_scheduler.py
@@ -61,6 +61,8 @@
                          'SUCCESS')
         self.assertEqual(A.data['status'], 'MERGED')
         self.assertEqual(A.reported, 2)
+        self.assertEqual(self.getJobFromHistory('project-test1').node,
+                         'image1')
 
         # TODOv3(jeblair): we may want to report stats by tenant (also?).
         self.assertReportedStat('gerrit.event.comment-added', value='1|c')
@@ -88,6 +90,25 @@
         self.assertReportedStat('zuul.pipeline.check.current_changes',
                                 value='0|g')
 
+    def test_job_branch(self):
+        "Test the correct variant of a job runs on a branch"
+        self.create_branch('org/project', 'stable')
+        A = self.fake_gerrit.addFakeChange('org/project', 'stable', 'A')
+        A.addApproval('code-review', 2)
+        self.fake_gerrit.addEvent(A.addApproval('approved', 1))
+        self.waitUntilSettled()
+        self.assertEqual(self.getJobFromHistory('project-test1').result,
+                         'SUCCESS')
+        self.assertEqual(self.getJobFromHistory('project-test2').result,
+                         'SUCCESS')
+        self.assertEqual(A.data['status'], 'MERGED')
+        self.assertEqual(A.reported, 2,
+                         "A should report start and success")
+        self.assertIn('gate', A.messages[1],
+                      "A should transit gate")
+        self.assertEqual(self.getJobFromHistory('project-test1').node,
+                         'image2')
+
     @skip("Disabled for early v3 development")
     def test_duplicate_pipelines(self):
         "Test that a change matching multiple pipelines works"
@@ -241,14 +262,13 @@
             dict(name='project-merge', result='SUCCESS', changes='2,1'),
             dict(name='project-test1', result='SUCCESS', changes='2,1'),
             dict(name='project-test2', result='SUCCESS', changes='2,1'),
-        ])
+        ], ordered=False)
 
         self.assertEqual(A.data['status'], 'NEW')
         self.assertEqual(B.data['status'], 'MERGED')
         self.assertEqual(A.reported, 2)
         self.assertEqual(B.reported, 2)
 
-    @skip("Disabled for early v3 development")
     def test_independent_queues(self):
         "Test that changes end up in the right queues"
 
@@ -267,28 +287,43 @@
         self.waitUntilSettled()
 
         # There should be one merge job at the head of each queue running
-        self.assertEqual(len(self.builds), 2)
-        self.assertEqual(self.builds[0].name, 'project-merge')
-        self.assertTrue(self.job_has_changes(self.builds[0], A))
-        self.assertEqual(self.builds[1].name, 'project1-merge')
-        self.assertTrue(self.job_has_changes(self.builds[1], B))
+        self.assertBuilds([
+            dict(name='project-merge', changes='1,1'),
+            dict(name='project-merge', changes='2,1'),
+        ])
 
         # Release the current merge builds
-        self.launch_server.release('.*-merge')
+        self.builds[0].release()
+        self.waitUntilSettled()
+        self.builds[0].release()
         self.waitUntilSettled()
         # Release the merge job for project2 which is behind project1
         self.launch_server.release('.*-merge')
         self.waitUntilSettled()
 
         # All the test builds should be running:
-        # project1 (3) + project2 (3) + project (2) = 8
-        self.assertEqual(len(self.builds), 8)
+        self.assertBuilds([
+            dict(name='project-test1', changes='1,1'),
+            dict(name='project-test2', changes='1,1'),
+            dict(name='project-test1', changes='2,1'),
+            dict(name='project-test2', changes='2,1'),
+            dict(name='project-test1', changes='2,1 3,1'),
+            dict(name='project-test2', changes='2,1 3,1'),
+        ])
 
-        self.launch_server.release()
-        self.waitUntilSettled()
-        self.assertEqual(len(self.builds), 0)
+        self.orderedRelease()
+        self.assertHistory([
+            dict(name='project-merge', result='SUCCESS', changes='1,1'),
+            dict(name='project-merge', result='SUCCESS', changes='2,1'),
+            dict(name='project-merge', result='SUCCESS', changes='2,1 3,1'),
+            dict(name='project-test1', result='SUCCESS', changes='1,1'),
+            dict(name='project-test2', result='SUCCESS', changes='1,1'),
+            dict(name='project-test1', result='SUCCESS', changes='2,1'),
+            dict(name='project-test2', result='SUCCESS', changes='2,1'),
+            dict(name='project-test1', result='SUCCESS', changes='2,1 3,1'),
+            dict(name='project-test2', result='SUCCESS', changes='2,1 3,1'),
+        ])
 
-        self.assertEqual(len(self.history), 11)
         self.assertEqual(A.data['status'], 'MERGED')
         self.assertEqual(B.data['status'], 'MERGED')
         self.assertEqual(C.data['status'], 'MERGED')
@@ -296,7 +331,6 @@
         self.assertEqual(B.reported, 2)
         self.assertEqual(C.reported, 2)
 
-    @skip("Disabled for early v3 development")
     def test_failed_change_at_head(self):
         "Test that if a change at the head fails, jobs behind it are canceled"
 
@@ -316,9 +350,9 @@
 
         self.waitUntilSettled()
 
-        self.assertEqual(len(self.builds), 1)
-        self.assertEqual(self.builds[0].name, 'project-merge')
-        self.assertTrue(self.job_has_changes(self.builds[0], A))
+        self.assertBuilds([
+            dict(name='project-merge', changes='1,1'),
+        ])
 
         self.launch_server.release('.*-merge')
         self.waitUntilSettled()
@@ -327,27 +361,84 @@
         self.launch_server.release('.*-merge')
         self.waitUntilSettled()
 
-        self.assertEqual(len(self.builds), 6)
-        self.assertEqual(self.builds[0].name, 'project-test1')
-        self.assertEqual(self.builds[1].name, 'project-test2')
-        self.assertEqual(self.builds[2].name, 'project-test1')
-        self.assertEqual(self.builds[3].name, 'project-test2')
-        self.assertEqual(self.builds[4].name, 'project-test1')
-        self.assertEqual(self.builds[5].name, 'project-test2')
+        self.assertBuilds([
+            dict(name='project-test1', changes='1,1'),
+            dict(name='project-test2', changes='1,1'),
+            dict(name='project-test1', changes='1,1 2,1'),
+            dict(name='project-test2', changes='1,1 2,1'),
+            dict(name='project-test1', changes='1,1 2,1 3,1'),
+            dict(name='project-test2', changes='1,1 2,1 3,1'),
+        ])
 
         self.release(self.builds[0])
         self.waitUntilSettled()
 
         # project-test2, project-merge for B
-        self.assertEqual(len(self.builds), 2)
-        self.assertEqual(self.countJobResults(self.history, 'ABORTED'), 4)
+        self.assertBuilds([
+            dict(name='project-test2', changes='1,1'),
+            dict(name='project-merge', changes='2,1'),
+        ])
+        # Unordered history comparison because the aborts can finish
+        # in any order.
+        self.assertHistory([
+            dict(name='project-merge', result='SUCCESS',
+                 changes='1,1'),
+            dict(name='project-merge', result='SUCCESS',
+                 changes='1,1 2,1'),
+            dict(name='project-merge', result='SUCCESS',
+                 changes='1,1 2,1 3,1'),
+            dict(name='project-test1', result='FAILURE',
+                 changes='1,1'),
+            dict(name='project-test1', result='ABORTED',
+                 changes='1,1 2,1'),
+            dict(name='project-test2', result='ABORTED',
+                 changes='1,1 2,1'),
+            dict(name='project-test1', result='ABORTED',
+                 changes='1,1 2,1 3,1'),
+            dict(name='project-test2', result='ABORTED',
+                 changes='1,1 2,1 3,1'),
+        ], ordered=False)
 
-        self.launch_server.hold_jobs_in_build = False
-        self.launch_server.release()
+        self.launch_server.release('.*-merge')
         self.waitUntilSettled()
+        self.launch_server.release('.*-merge')
+        self.waitUntilSettled()
+        self.orderedRelease()
 
-        self.assertEqual(len(self.builds), 0)
-        self.assertEqual(len(self.history), 15)
+        self.assertBuilds([])
+        self.assertHistory([
+            dict(name='project-merge', result='SUCCESS',
+                 changes='1,1'),
+            dict(name='project-merge', result='SUCCESS',
+                 changes='1,1 2,1'),
+            dict(name='project-merge', result='SUCCESS',
+                 changes='1,1 2,1 3,1'),
+            dict(name='project-test1', result='FAILURE',
+                 changes='1,1'),
+            dict(name='project-test1', result='ABORTED',
+                 changes='1,1 2,1'),
+            dict(name='project-test2', result='ABORTED',
+                 changes='1,1 2,1'),
+            dict(name='project-test1', result='ABORTED',
+                 changes='1,1 2,1 3,1'),
+            dict(name='project-test2', result='ABORTED',
+                 changes='1,1 2,1 3,1'),
+            dict(name='project-merge', result='SUCCESS',
+                 changes='2,1'),
+            dict(name='project-merge', result='SUCCESS',
+                 changes='2,1 3,1'),
+            dict(name='project-test2', result='SUCCESS',
+                 changes='1,1'),
+            dict(name='project-test1', result='SUCCESS',
+                 changes='2,1'),
+            dict(name='project-test2', result='SUCCESS',
+                 changes='2,1'),
+            dict(name='project-test1', result='SUCCESS',
+                 changes='2,1 3,1'),
+            dict(name='project-test2', result='SUCCESS',
+                 changes='2,1 3,1'),
+        ], ordered=False)
+
         self.assertEqual(A.data['status'], 'NEW')
         self.assertEqual(B.data['status'], 'MERGED')
         self.assertEqual(C.data['status'], 'MERGED')
diff --git a/zuul/configloader.py b/zuul/configloader.py
index bc2f7fc..b41dcc1 100644
--- a/zuul/configloader.py
+++ b/zuul/configloader.py
@@ -37,6 +37,29 @@
     return [item]
 
 
+class NodeSetParser(object):
+    @staticmethod
+    def getSchema():
+        node = {vs.Required('name'): str,
+                vs.Required('image'): str,
+                }
+
+        nodeset = {vs.Required('name'): str,
+                   vs.Required('nodes'): [node],
+                   }
+
+        return vs.Schema(nodeset)
+
+    @staticmethod
+    def fromYaml(layout, conf):
+        NodeSetParser.getSchema()(conf)
+        ns = model.NodeSet(conf['name'])
+        for conf_node in as_list(conf['nodes']):
+            node = model.Node(conf_node['name'], conf_node['image'])
+            ns.addNode(node)
+        return ns
+
+
 class JobParser(object):
     @staticmethod
     def getSchema():
@@ -77,7 +100,7 @@
                'files': to_list(str),
                'auth': to_list(auth),
                'irrelevant-files': to_list(str),
-               'nodes': [node],
+               'nodes': vs.Any([node], str),
                'timeout': int,
                '_source_project': model.Project,
                }
@@ -100,6 +123,18 @@
         job.voting = conf.get('voting', True)
         job.hold_following_changes = conf.get('hold-following-changes', False)
         job.mutex = conf.get('mutex', None)
+        if 'nodes' in conf:
+            conf_nodes = conf['nodes']
+            if isinstance(conf_nodes, six.string_types):
+                # This references an existing named nodeset in the layout.
+                ns = layout.nodesets[conf_nodes]
+            else:
+                ns = model.NodeSet()
+                for conf_node in conf_nodes:
+                    node = model.Node(conf_node['name'], conf_node['image'])
+                    ns.addNode(node)
+            job.nodeset = ns
+
         tags = conf.get('tags')
         if tags:
             # Tags are merged via a union rather than a
@@ -156,9 +191,9 @@
                 continue
             project_pipeline = model.ProjectPipelineConfig()
             project_template.pipelines[pipeline.name] = project_pipeline
-            project_pipeline.queue_name = conf.get('queue')
+            project_pipeline.queue_name = conf_pipeline.get('queue')
             project_pipeline.job_tree = ProjectTemplateParser._parseJobTree(
-                layout, conf_pipeline.get('jobs'))
+                layout, conf_pipeline.get('jobs', []))
         return project_template
 
     @staticmethod
@@ -571,6 +606,9 @@
                                                        scheduler,
                                                        config_pipeline))
 
+        for config_nodeset in data.nodesets:
+            layout.addNodeSet(NodeSetParser.fromYaml(layout, config_nodeset))
+
         for config_job in data.jobs:
             layout.addJob(JobParser.fromYaml(layout, config_job))
 
diff --git a/zuul/launcher/client.py b/zuul/launcher/client.py
index cd6dcfd..96a524d 100644
--- a/zuul/launcher/client.py
+++ b/zuul/launcher/client.py
@@ -297,9 +297,11 @@
     def launch(self, job, item, pipeline, dependent_items=[]):
         uuid = str(uuid4().hex)
         self.log.info(
-            "Launch job %s (uuid: %s) for change %s with dependent "
-            "changes %s" % (
-                job, uuid, item.change,
+            "Launch job %s (uuid: %s) on nodes %s for change %s "
+            "with dependent changes %s" % (
+                job, uuid,
+                item.current_build_set.getJobNodeSet(job.name),
+                item.change,
                 [x.change for x in dependent_items]))
         dependent_items = dependent_items[:]
         dependent_items.reverse()
@@ -371,6 +373,10 @@
         params['job'] = job.name
         params['items'] = merger_items
         params['projects'] = []
+        nodes = []
+        for node in item.current_build_set.getJobNodeSet(job.name).getNodes():
+            nodes.append(dict(name=node.name, image=node.image))
+        params['nodes'] = nodes
         projects = set()
         for item in all_items:
             if item.change.project not in projects:
diff --git a/zuul/launcher/server.py b/zuul/launcher/server.py
index 2a988b0..bc533a9 100644
--- a/zuul/launcher/server.py
+++ b/zuul/launcher/server.py
@@ -280,9 +280,14 @@
         job.sendWorkComplete()
 
     def getHostList(self, args):
-        # TODOv3: This should get the appropriate nodes from nodepool,
-        # or in the unit tests, be overriden to return localhost.
-        return [('localhost', dict(ansible_connection='local'))]
+        # TODOv3: the localhost addition is temporary so we have
+        # something to exercise ansible.
+        hosts = [('localhost', dict(ansible_connection='local'))]
+        for node in args['nodes']:
+            # TODOv3: the connection should almost certainly not be
+            # local.
+            hosts.append((node['name'], dict(ansible_connection='local')))
+        return hosts
 
     def prepareAnsibleFiles(self, jobdir, args):
         with open(jobdir.inventory, 'w') as inventory:
diff --git a/zuul/manager/__init__.py b/zuul/manager/__init__.py
index 0cd1877..70a510e 100644
--- a/zuul/manager/__init__.py
+++ b/zuul/manager/__init__.py
@@ -616,9 +616,11 @@
         request = event.request
         build_set = request.build_set
         build_set.jobNodeRequestComplete(request.job.name, request,
-                                         request.nodes)
-        self.log.info("Completed node request %s for job %s of item %s" %
-                      (request, request.job.name, build_set.item))
+                                         request.nodeset)
+        self.log.info("Completed node request %s for job %s of item %s "
+                      "with nodes %s" %
+                      (request, request.job, build_set.item,
+                       request.nodeset))
 
     def reportItem(self, item):
         if not item.reported:
diff --git a/zuul/manager/dependent.py b/zuul/manager/dependent.py
index 686a593..3d006c2 100644
--- a/zuul/manager/dependent.py
+++ b/zuul/manager/dependent.py
@@ -36,51 +36,38 @@
 
     def buildChangeQueues(self):
         self.log.debug("Building shared change queues")
-        change_queues = []
+        change_queues = {}
+        project_configs = self.pipeline.layout.project_configs
 
         for project in self.pipeline.getProjects():
-            change_queue = model.ChangeQueue(
-                self.pipeline,
-                window=self.pipeline.window,
-                window_floor=self.pipeline.window_floor,
-                window_increase_type=self.pipeline.window_increase_type,
-                window_increase_factor=self.pipeline.window_increase_factor,
-                window_decrease_type=self.pipeline.window_decrease_type,
-                window_decrease_factor=self.pipeline.window_decrease_factor)
+            project_config = project_configs[project.name]
+            project_pipeline_config = project_config.pipelines[
+                self.pipeline.name]
+            queue_name = project_pipeline_config.queue_name
+            if queue_name and queue_name in change_queues:
+                change_queue = change_queues[queue_name]
+            else:
+                p = self.pipeline
+                change_queue = model.ChangeQueue(
+                    p,
+                    window=p.window,
+                    window_floor=p.window_floor,
+                    window_increase_type=p.window_increase_type,
+                    window_increase_factor=p.window_increase_factor,
+                    window_decrease_type=p.window_decrease_type,
+                    window_decrease_factor=p.window_decrease_factor,
+                    name=queue_name)
+                if queue_name:
+                    # If this is a named queue, keep track of it in
+                    # case it is referenced again.  Otherwise, it will
+                    # have a name automatically generated from its
+                    # constituent projects.
+                    change_queues[queue_name] = change_queue
+                self.pipeline.addQueue(change_queue)
+                self.log.debug("Created queue: %s" % change_queue)
             change_queue.addProject(project)
-            change_queues.append(change_queue)
-            self.log.debug("Created queue: %s" % change_queue)
-
-        # Iterate over all queues trying to combine them, and keep doing
-        # so until they can not be combined further.
-        last_change_queues = change_queues
-        while True:
-            new_change_queues = self.combineChangeQueues(last_change_queues)
-            if len(last_change_queues) == len(new_change_queues):
-                break
-            last_change_queues = new_change_queues
-
-        self.log.info("  Shared change queues:")
-        for queue in new_change_queues:
-            self.pipeline.addQueue(queue)
-            self.log.info("    %s containing %s" % (
-                queue, queue.generated_name))
-
-    def combineChangeQueues(self, change_queues):
-        self.log.debug("Combining shared queues")
-        new_change_queues = []
-        for a in change_queues:
-            merged_a = False
-            for b in new_change_queues:
-                if not a.getJobs().isdisjoint(b.getJobs()):
-                    self.log.debug("Merging queue %s into %s" % (a, b))
-                    b.mergeChangeQueue(a)
-                    merged_a = True
-                    break  # this breaks out of 'for b' and continues 'for a'
-            if not merged_a:
-                self.log.debug("Keeping queue %s" % (a))
-                new_change_queues.append(a)
-        return new_change_queues
+            self.log.debug("Added project %s to queue: %s" %
+                           (project, change_queue))
 
     def getChangeQueue(self, change, existing=None):
         if existing:
diff --git a/zuul/model.py b/zuul/model.py
index ce3d1a2..0aa1ad5 100644
--- a/zuul/model.py
+++ b/zuul/model.py
@@ -131,11 +131,6 @@
     def setManager(self, manager):
         self.manager = manager
 
-    def addProject(self, project):
-        job_tree = JobTree(None)  # Null job == job tree root
-        self.job_trees[project] = job_tree
-        return job_tree
-
     def getProjects(self):
         # cmp is not in python3, applied idiom from
         # http://python-future.org/compatible_idioms.html#cmp
@@ -219,11 +214,13 @@
     """
     def __init__(self, pipeline, window=0, window_floor=1,
                  window_increase_type='linear', window_increase_factor=1,
-                 window_decrease_type='exponential', window_decrease_factor=2):
+                 window_decrease_type='exponential', window_decrease_factor=2,
+                 name=None):
         self.pipeline = pipeline
-        self.name = ''
-        self.assigned_name = None
-        self.generated_name = None
+        if name:
+            self.name = name
+        else:
+            self.name = ''
         self.projects = []
         self._jobs = set()
         self.queue = []
@@ -244,10 +241,8 @@
         if project not in self.projects:
             self.projects.append(project)
 
-            names = [x.name for x in self.projects]
-            names.sort()
-            self.generated_name = ', '.join(names)
-            self.name = self.assigned_name or self.generated_name
+            if not self.name:
+                self.name = project.name
 
     def enqueueChange(self, change):
         item = QueueItem(self, change)
@@ -349,13 +344,71 @@
         return '<Project %s>' % (self.name)
 
 
+class Node(object):
+    """A single node for use by a job.
+
+    This may represent a request for a node, or an actual node
+    provided by Nodepool.
+    """
+
+    def __init__(self, name, image):
+        self.name = name
+        self.image = image
+
+    def __repr__(self):
+        return '<Node %s:%s>' % (self.name, self.image)
+
+
+class NodeSet(object):
+    """A set of nodes.
+
+    In configuration, NodeSets are attributes of Jobs indicating that
+    a Job requires nodes matching this description.
+
+    They may appear as top-level configuration objects and be named,
+    or they may appears anonymously in in-line job definitions.
+    """
+
+    def __init__(self, name=None):
+        self.name = name or ''
+        self.nodes = OrderedDict()
+
+    def addNode(self, node):
+        if node.name in self.nodes:
+            raise Exception("Duplicate node in %s" % (self,))
+        self.nodes[node.name] = node
+
+    def getNodes(self):
+        return self.nodes.values()
+
+    def __repr__(self):
+        if self.name:
+            name = self.name + ' '
+        else:
+            name = ''
+        return '<NodeSet %s%s>' % (name, self.nodes)
+
+
+class NodeRequest(object):
+    """A request for a set of nodes."""
+
+    def __init__(self, build_set, job, nodeset):
+        self.build_set = build_set
+        self.job = job
+        self.nodeset = nodeset
+        self.id = uuid4().hex
+
+    def __repr__(self):
+        return '<NodeRequest %s>' % (self.nodeset,)
+
+
 class Job(object):
     """A Job represents the defintion of actions to perform."""
 
     attributes = dict(
         timeout=None,
         # variables={},
-        nodes=[],
+        nodeset=NodeSet(),
         auth={},
         workspace=None,
         pre_run=None,
@@ -399,7 +452,7 @@
         return self.name
 
     def __repr__(self):
-        return '<Job %s>' % (self.name,)
+        return '<Job %s branches: %s>' % (self.name, self.branch_matcher)
 
     def inheritFrom(self, other):
         """Copy the inheritable attributes which have been set on the other
@@ -583,7 +636,7 @@
         self.unable_to_merge = False
         self.failing_reasons = []
         self.merge_state = self.NEW
-        self.nodes = {}  # job -> nodes
+        self.nodesets = {}  # job -> nodeset
         self.node_requests = {}  # job -> reqs
         self.files = RepoFiles()
         self.layout = None
@@ -625,9 +678,10 @@
         keys.sort()
         return [self.builds.get(x) for x in keys]
 
-    def getJobNodes(self, job_name):
-        # Return None if not provisioned; [] if no nodes required
-        return self.nodes.get(job_name)
+    def getJobNodeSet(self, job_name):
+        # Return None if not provisioned; empty NodeSet if no nodes
+        # required
+        return self.nodesets.get(job_name)
 
     def setJobNodeRequest(self, job_name, req):
         if job_name in self.node_requests:
@@ -637,10 +691,10 @@
     def getJobNodeRequest(self, job_name):
         return self.node_requests.get(job_name)
 
-    def jobNodeRequestComplete(self, job_name, req, nodes):
-        if job_name in self.nodes:
+    def jobNodeRequestComplete(self, job_name, req, nodeset):
+        if job_name in self.nodesets:
             raise Exception("Prior node request for %s" % (job_name))
-        self.nodes[job_name] = nodes
+        self.nodesets[job_name] = nodeset
         del self.node_requests[job_name]
 
 
@@ -794,7 +848,12 @@
                     result = build.result
                 else:
                     # There is no build for the root of this job tree,
-                    # so we should run it.
+                    # so it has not run yet.
+                    nodeset = self.current_build_set.getJobNodeSet(job.name)
+                    if nodeset is None:
+                        # The nodes for this job are not ready, skip
+                        # it for now.
+                        continue
                     if mutex.acquire(self, job):
                         # If this job needs a mutex, either acquire it or make
                         # sure that we have it before running the job.
@@ -820,15 +879,12 @@
             if job:
                 if not job.changeMatches(self.change):
                     continue
-                nodes = self.current_build_set.getJobNodes(job.name)
-                if nodes is None:
+                nodeset = self.current_build_set.getJobNodeSet(job.name)
+                if nodeset is None:
                     req = self.current_build_set.getJobNodeRequest(job.name)
                     if req is None:
                         toreq.append(job)
-            # If there is no job, this is a null job tree, and we should
-            # run all of its jobs.
-            if not job:
-                toreq.extend(self._findJobsToRequest(tree.job_trees))
+            toreq.extend(self._findJobsToRequest(tree.job_trees))
         return toreq
 
     def findJobsToRequest(self):
@@ -1573,6 +1629,7 @@
         self.jobs = []
         self.project_templates = []
         self.projects = []
+        self.nodesets = []
 
     def copy(self):
         r = UnparsedTenantConfig()
@@ -1580,6 +1637,7 @@
         r.jobs = copy.deepcopy(self.jobs)
         r.project_templates = copy.deepcopy(self.project_templates)
         r.projects = copy.deepcopy(self.projects)
+        r.nodesets = copy.deepcopy(self.nodesets)
         return r
 
     def extend(self, conf, source_project=None):
@@ -1588,6 +1646,7 @@
             self.jobs.extend(conf.jobs)
             self.project_templates.extend(conf.project_templates)
             self.projects.extend(conf.projects)
+            self.nodesets.extend(conf.nodesets)
             return
 
         if not isinstance(conf, list):
@@ -1614,6 +1673,8 @@
                 self.project_templates.append(value)
             elif key == 'pipeline':
                 self.pipelines.append(value)
+            elif key == 'nodeset':
+                self.nodesets.append(value)
             else:
                 raise Exception("Configuration item `%s` not recognized "
                                 "(when parsing %s)" %
@@ -1636,6 +1697,7 @@
         # that override some attribute of the job.  These aspects all
         # inherit from the reference definition.
         self.jobs = {}
+        self.nodesets = {}
 
     def getJob(self, name):
         if name in self.jobs:
@@ -1661,6 +1723,11 @@
         else:
             self.jobs[job.name] = [job]
 
+    def addNodeSet(self, nodeset):
+        if nodeset.name in self.nodesets:
+            raise Exception("NodeSet %s already defined" % (nodeset.name,))
+        self.nodesets[nodeset.name] = nodeset
+
     def addPipeline(self, pipeline):
         self.pipelines[pipeline.name] = pipeline
 
diff --git a/zuul/nodepool.py b/zuul/nodepool.py
index 85a18f1..addeaf3 100644
--- a/zuul/nodepool.py
+++ b/zuul/nodepool.py
@@ -10,21 +10,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from uuid import uuid4
-
-
-class Node(object):
-    def __init__(self, name, image):
-        self.name = name
-        self.image = image
-
-
-class Request(object):
-    def __init__(self, build_set, job, nodes):
-        self.build_set = build_set
-        self.job = job
-        self.nodes = nodes
-        self.id = uuid4().hex
+from zuul.model import NodeRequest
 
 
 class Nodepool(object):
@@ -33,9 +19,7 @@
         self.sched = scheduler
 
     def requestNodes(self, build_set, job):
-        nodes = job.nodes
-        nodes = [Node(node['name'], node['image']) for node in nodes]
-        req = Request(build_set, job, nodes)
+        req = NodeRequest(build_set, job, job.nodeset)
         self.requests[req.id] = req
         self._requestComplete(req.id)
         return req