diff --git a/tests/fixtures/config/split-config/git/common-config/playbooks/project-test1.yaml b/tests/fixtures/config/split-config/git/common-config/playbooks/project-test1.yaml
new file mode 100644
index 0000000..f679dce
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/common-config/playbooks/project-test1.yaml
@@ -0,0 +1,2 @@
+- hosts: all
+  tasks: []
diff --git a/tests/fixtures/config/split-config/git/common-config/zuul.d/jobs.yaml b/tests/fixtures/config/split-config/git/common-config/zuul.d/jobs.yaml
new file mode 100644
index 0000000..280342c
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/common-config/zuul.d/jobs.yaml
@@ -0,0 +1,2 @@
+- job:
+    name: project-test1
diff --git a/tests/fixtures/config/split-config/git/common-config/zuul.d/org-project.yaml b/tests/fixtures/config/split-config/git/common-config/zuul.d/org-project.yaml
new file mode 100644
index 0000000..872e126
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/common-config/zuul.d/org-project.yaml
@@ -0,0 +1,5 @@
+- project:
+    name: org/project
+    check:
+      jobs:
+        - project-test1
diff --git a/tests/fixtures/config/split-config/git/common-config/zuul.d/pipelines.yaml b/tests/fixtures/config/split-config/git/common-config/zuul.d/pipelines.yaml
new file mode 100644
index 0000000..ba91fb5
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/common-config/zuul.d/pipelines.yaml
@@ -0,0 +1,12 @@
+- pipeline:
+    name: check
+    manager: independent
+    trigger:
+      gerrit:
+        - event: patchset-created
+    success:
+      gerrit:
+        verified: 1
+    failure:
+      gerrit:
+        verified: -1
diff --git a/tests/fixtures/config/split-config/git/org_project/README b/tests/fixtures/config/split-config/git/org_project/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/org_project/README
@@ -0,0 +1 @@
+test
diff --git a/tests/fixtures/config/split-config/git/org_project1/.zuul.d/gate.yaml b/tests/fixtures/config/split-config/git/org_project1/.zuul.d/gate.yaml
new file mode 100644
index 0000000..4bc0d81
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/org_project1/.zuul.d/gate.yaml
@@ -0,0 +1,7 @@
+- project:
+    name: org/project1
+    check:
+      jobs:
+        - project-test1
+        - project1-project2-integration:
+            dependencies: project-test1
diff --git a/tests/fixtures/config/split-config/git/org_project1/.zuul.d/jobs.yaml b/tests/fixtures/config/split-config/git/org_project1/.zuul.d/jobs.yaml
new file mode 100644
index 0000000..33d74f3
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/org_project1/.zuul.d/jobs.yaml
@@ -0,0 +1,2 @@
+- job:
+    name: project1-project2-integration
diff --git a/tests/fixtures/config/split-config/git/org_project1/README b/tests/fixtures/config/split-config/git/org_project1/README
new file mode 100644
index 0000000..9daeafb
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/org_project1/README
@@ -0,0 +1 @@
+test
diff --git a/tests/fixtures/config/split-config/git/org_project1/playbooks/project1-project2-integration.yaml b/tests/fixtures/config/split-config/git/org_project1/playbooks/project1-project2-integration.yaml
new file mode 100644
index 0000000..f679dce
--- /dev/null
+++ b/tests/fixtures/config/split-config/git/org_project1/playbooks/project1-project2-integration.yaml
@@ -0,0 +1,2 @@
+- hosts: all
+  tasks: []
diff --git a/tests/fixtures/config/split-config/main.yaml b/tests/fixtures/config/split-config/main.yaml
new file mode 100644
index 0000000..5f57245
--- /dev/null
+++ b/tests/fixtures/config/split-config/main.yaml
@@ -0,0 +1,9 @@
+- tenant:
+    name: tenant-one
+    source:
+      gerrit:
+        config-projects:
+          - common-config
+        untrusted-projects:
+          - org/project
+          - org/project1
diff --git a/tests/fixtures/config/templated-project/git/common-config/zuul.d/jobs.yaml b/tests/fixtures/config/templated-project/git/common-config/zuul.d/jobs.yaml
new file mode 100644
index 0000000..e051871
--- /dev/null
+++ b/tests/fixtures/config/templated-project/git/common-config/zuul.d/jobs.yaml
@@ -0,0 +1,17 @@
+- job:
+    name: project-test1
+
+- job:
+    name: project-test2
+
+- job:
+    name: layered-project-test3
+
+- job:
+    name: layered-project-test4
+
+- job:
+    name: layered-project-foo-test5
+
+- job:
+    name: project-test6
diff --git a/tests/fixtures/config/templated-project/git/common-config/zuul.d/pipelines.yaml b/tests/fixtures/config/templated-project/git/common-config/zuul.d/pipelines.yaml
new file mode 100644
index 0000000..4a19796
--- /dev/null
+++ b/tests/fixtures/config/templated-project/git/common-config/zuul.d/pipelines.yaml
@@ -0,0 +1,41 @@
+- pipeline:
+    name: check
+    manager: independent
+    trigger:
+      gerrit:
+        - event: patchset-created
+    success:
+      gerrit:
+        verified: 1
+    failure:
+      gerrit:
+        verified: -1
+
+- pipeline:
+    name: gate
+    manager: dependent
+    success-message: Build succeeded (gate).
+    trigger:
+      gerrit:
+        - event: comment-added
+          approval:
+            - approved: 1
+    success:
+      gerrit:
+        verified: 2
+        submit: true
+    failure:
+      gerrit:
+        verified: -2
+    start:
+      gerrit:
+        verified: 0
+    precedence: high
+
+- pipeline:
+    name: post
+    manager: independent
+    trigger:
+      gerrit:
+        - event: ref-updated
+          ref: ^(?!refs/).*$
diff --git a/tests/fixtures/config/templated-project/git/common-config/zuul.d/projects.yaml b/tests/fixtures/config/templated-project/git/common-config/zuul.d/projects.yaml
new file mode 100644
index 0000000..891c863
--- /dev/null
+++ b/tests/fixtures/config/templated-project/git/common-config/zuul.d/projects.yaml
@@ -0,0 +1,14 @@
+- project:
+    name: org/templated-project
+    templates:
+      - test-one-and-two
+
+- project:
+    name: org/layered-project
+    templates:
+      - test-one-and-two
+      - test-three-and-four
+      - test-five
+    check:
+      jobs:
+        - project-test6
diff --git a/tests/fixtures/config/templated-project/git/common-config/zuul.d/templates.yaml b/tests/fixtures/config/templated-project/git/common-config/zuul.d/templates.yaml
new file mode 100644
index 0000000..27d2f16
--- /dev/null
+++ b/tests/fixtures/config/templated-project/git/common-config/zuul.d/templates.yaml
@@ -0,0 +1,19 @@
+- project-template:
+    name: test-one-and-two
+    check:
+      jobs:
+        - project-test1
+        - project-test2
+
+- project-template:
+    name: test-three-and-four
+    check:
+      jobs:
+        - layered-project-test3
+        - layered-project-test4
+
+- project-template:
+    name: test-five
+    check:
+      jobs:
+        - layered-project-foo-test5
diff --git a/tests/fixtures/config/templated-project/git/common-config/zuul.yaml b/tests/fixtures/config/templated-project/git/common-config/zuul.yaml
deleted file mode 100644
index 251a3cd..0000000
--- a/tests/fixtures/config/templated-project/git/common-config/zuul.yaml
+++ /dev/null
@@ -1,94 +0,0 @@
-- pipeline:
-    name: check
-    manager: independent
-    trigger:
-      gerrit:
-        - event: patchset-created
-    success:
-      gerrit:
-        verified: 1
-    failure:
-      gerrit:
-        verified: -1
-
-- pipeline:
-    name: gate
-    manager: dependent
-    success-message: Build succeeded (gate).
-    trigger:
-      gerrit:
-        - event: comment-added
-          approval:
-            - approved: 1
-    success:
-      gerrit:
-        verified: 2
-        submit: true
-    failure:
-      gerrit:
-        verified: -2
-    start:
-      gerrit:
-        verified: 0
-    precedence: high
-
-- pipeline:
-    name: post
-    manager: independent
-    trigger:
-      gerrit:
-        - event: ref-updated
-          ref: ^(?!refs/).*$
-
-- project-template:
-    name: test-one-and-two
-    check:
-      jobs:
-        - project-test1
-        - project-test2
-
-- project-template:
-    name: test-three-and-four
-    check:
-      jobs:
-        - layered-project-test3
-        - layered-project-test4
-
-- project-template:
-    name: test-five
-    check:
-      jobs:
-        - layered-project-foo-test5
-
-- job:
-    name: project-test1
-
-- job:
-    name: project-test2
-
-- job:
-    name: layered-project-test3
-
-- job:
-    name: layered-project-test4
-
-- job:
-    name: layered-project-foo-test5
-
-- job:
-    name: project-test6
-
-- project:
-    name: org/templated-project
-    templates:
-      - test-one-and-two
-
-- project:
-    name: org/layered-project
-    templates:
-      - test-one-and-two
-      - test-three-and-four
-      - test-five
-    check:
-      jobs:
-        - project-test6
diff --git a/tests/unit/test_configloader.py b/tests/unit/test_configloader.py
index faa2f61..f0e606a 100644
--- a/tests/unit/test_configloader.py
+++ b/tests/unit/test_configloader.py
@@ -12,6 +12,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import textwrap
 
 from tests.base import ZuulTestCase
 
@@ -186,3 +187,40 @@
                         project2_config.pipelines['check'].job_list.jobs)
         self.assertTrue('project2-job' in
                         project2_config.pipelines['check'].job_list.jobs)
+
+
+class TestSplitConfig(ZuulTestCase):
+    tenant_config_file = 'config/split-config/main.yaml'
+
+    def setup_config(self):
+        super(TestSplitConfig, self).setup_config()
+
+    def test_split_config(self):
+        tenant = self.sched.abide.tenants.get('tenant-one')
+        self.assertIn('project-test1', tenant.layout.jobs)
+        project_config = tenant.layout.project_configs.get(
+            'review.example.com/org/project')
+        self.assertIn('project-test1',
+                      project_config.pipelines['check'].job_list.jobs)
+        project1_config = tenant.layout.project_configs.get(
+            'review.example.com/org/project1')
+        self.assertIn('project1-project2-integration',
+                      project1_config.pipelines['check'].job_list.jobs)
+
+    def test_dynamic_split_config(self):
+        in_repo_conf = textwrap.dedent(
+            """
+            - project:
+                name: org/project1
+                check:
+                  jobs:
+                    - project-test1
+            """)
+        file_dict = {'.zuul.d/gate.yaml': in_repo_conf}
+        A = self.fake_gerrit.addFakeChange('org/project1', 'master', 'A',
+                                           files=file_dict)
+        self.fake_gerrit.addEvent(A.getPatchsetCreatedEvent(1))
+        self.waitUntilSettled()
+        # project1-project2-integration test removed, only want project-test1
+        self.assertHistory([
+            dict(name='project-test1', result='SUCCESS', changes='1,1')])
diff --git a/zuul/configloader.py b/zuul/configloader.py
index 4246206..627ebdd 100644
--- a/zuul/configloader.py
+++ b/zuul/configloader.py
@@ -1106,7 +1106,8 @@
             job = merger.getFiles(
                 project.source.connection.connection_name,
                 project.name, 'master',
-                files=['zuul.yaml', '.zuul.yaml'])
+                files=['zuul.yaml', '.zuul.yaml'],
+                dirs=['zuul.d', '.zuul.d'])
             job.source_context = model.SourceContext(project, 'master',
                                                      '', True)
             jobs.append(job)
@@ -1134,7 +1135,8 @@
                 job = merger.getFiles(
                     project.source.connection.connection_name,
                     project.name, branch,
-                    files=['zuul.yaml', '.zuul.yaml'])
+                    files=['zuul.yaml', '.zuul.yaml'],
+                    dirs=['zuul.d', '.zuul.d'])
                 job.source_context = model.SourceContext(
                     project, branch, '', False)
                 jobs.append(job)
@@ -1147,15 +1149,19 @@
             TenantParser.log.debug("Waiting for cat job %s" % (job,))
             job.wait()
             loaded = False
-            for fn in ['zuul.yaml', '.zuul.yaml']:
-                if job.files.get(fn):
-                    # Don't load from more than one file in a repo-branch
-                    if loaded:
+            files = sorted(job.files.keys())
+            for conf_root in ['zuul.yaml', '.zuul.yaml', 'zuul.d', '.zuul.d']:
+                for fn in files:
+                    fn_root = fn.split('/')[0]
+                    if fn_root != conf_root or not job.files.get(fn):
+                        continue
+                    # Don't load from more than configuration in a repo-branch
+                    if loaded and loaded != conf_root:
                         TenantParser.log.warning(
                             "Multiple configuration files in %s" %
                             (job.source_context,))
                         continue
-                    loaded = True
+                    loaded = conf_root
                     job.source_context.path = fn
                     TenantParser.log.info(
                         "Loading configuration from %s" %
@@ -1328,28 +1334,50 @@
             branches = project.source.getProjectBranches(project)
 
         for branch in branches:
+            fns1 = []
+            fns2 = []
+            files_list = files.connections.get(
+                project.source.connection.connection_name, {}).get(
+                    project.name, {}).get(branch, {}).keys()
+            for fn in files_list:
+                if fn.startswith("zuul.d/"):
+                    fns1.append(fn)
+                if fn.startswith(".zuul.d/"):
+                    fns2.append(fn)
+
+            fns = ['zuul.yaml', '.zuul.yaml'] + sorted(fns1) + sorted(fns2)
             incdata = None
-            for fn in ['zuul.yaml', '.zuul.yaml']:
+            loaded = None
+            for fn in fns:
                 data = files.getFile(project.source.connection.connection_name,
                                      project.name, branch, fn)
                 if data:
-                    break
-            if data:
-                source_context = model.SourceContext(project, branch,
-                                                     fn, trusted)
-                if trusted:
-                    incdata = TenantParser._parseConfigProjectLayout(
-                        data, source_context)
-                else:
-                    incdata = TenantParser._parseUntrustedProjectLayout(
-                        data, source_context)
-            else:
+                    source_context = model.SourceContext(project, branch,
+                                                         fn, trusted)
+                    # Prevent mixing configuration source
+                    conf_root = fn.split('/')[0]
+                    if loaded and loaded != conf_root:
+                        TenantParser.log.warning(
+                            "Multiple configuration in %s" % source_context)
+                        continue
+                    loaded = conf_root
+
+                    if trusted:
+                        incdata = TenantParser._parseConfigProjectLayout(
+                            data, source_context)
+                    else:
+                        incdata = TenantParser._parseUntrustedProjectLayout(
+                            data, source_context)
+
+                    config.extend(incdata)
+
+            if not loaded:
                 if trusted:
                     incdata = project.unparsed_config
                 else:
                     incdata = project.unparsed_branch_config.get(branch)
-            if incdata:
-                config.extend(incdata)
+                if incdata:
+                    config.extend(incdata)
 
     def createDynamicLayout(self, tenant, files,
                             include_config_projects=False):
diff --git a/zuul/executor/server.py b/zuul/executor/server.py
index 6c390db..1ebe55d 100644
--- a/zuul/executor/server.py
+++ b/zuul/executor/server.py
@@ -641,7 +641,8 @@
         task.wait()
         with self.merger_lock:
             files = self.merger.getFiles(args['connection'], args['project'],
-                                         args['branch'], args['files'])
+                                         args['branch'], args['files'],
+                                         args.get('dirs', []))
         result = dict(updated=True,
                       files=files,
                       zuul_url=self.zuul_url)
@@ -651,6 +652,7 @@
         args = json.loads(job.arguments)
         with self.merger_lock:
             ret = self.merger.mergeChanges(args['items'], args.get('files'),
+                                           args.get('dirs', []),
                                            args.get('repo_state'))
         result = dict(merged=(ret is not None),
                       zuul_url=self.zuul_url)
diff --git a/zuul/manager/__init__.py b/zuul/manager/__init__.py
index 01429ce..09b09d7 100644
--- a/zuul/manager/__init__.py
+++ b/zuul/manager/__init__.py
@@ -480,7 +480,7 @@
             self.log.debug("Preparing dynamic layout for: %s" % item.change)
             return self._loadDynamicLayout(item)
 
-    def scheduleMerge(self, item, files=None):
+    def scheduleMerge(self, item, files=None, dirs=None):
         build_set = item.current_build_set
 
         if not hasattr(item.change, 'branch'):
@@ -490,12 +490,12 @@
             build_set.merge_state = build_set.COMPLETE
             return True
 
-        self.log.debug("Scheduling merge for item %s (files: %s)" %
-                       (item, files))
+        self.log.debug("Scheduling merge for item %s (files: %s, dirs: %s)" %
+                       (item, files, dirs))
         build_set = item.current_build_set
         build_set.merge_state = build_set.PENDING
         self.sched.merger.mergeChanges(build_set.merger_items,
-                                       item.current_build_set, files,
+                                       item.current_build_set, files, dirs,
                                        precedence=self.pipeline.precedence)
         return False
 
@@ -506,7 +506,9 @@
         if not build_set.ref:
             build_set.setConfiguration()
         if build_set.merge_state == build_set.NEW:
-            return self.scheduleMerge(item, ['zuul.yaml', '.zuul.yaml'])
+            return self.scheduleMerge(item,
+                                      files=['zuul.yaml', '.zuul.yaml'],
+                                      dirs=['zuul.d', '.zuul.d'])
         if build_set.merge_state == build_set.PENDING:
             return False
         if build_set.unable_to_merge:
diff --git a/zuul/merger/client.py b/zuul/merger/client.py
index e92d9fd..e354d5d 100644
--- a/zuul/merger/client.py
+++ b/zuul/merger/client.py
@@ -108,19 +108,21 @@
                                timeout=300)
         return job
 
-    def mergeChanges(self, items, build_set, files=None, repo_state=None,
-                     precedence=zuul.model.PRECEDENCE_NORMAL):
+    def mergeChanges(self, items, build_set, files=None, dirs=None,
+                     repo_state=None, precedence=zuul.model.PRECEDENCE_NORMAL):
         data = dict(items=items,
                     files=files,
+                    dirs=dirs,
                     repo_state=repo_state)
         self.submitJob('merger:merge', data, build_set, precedence)
 
-    def getFiles(self, connection_name, project_name, branch, files,
+    def getFiles(self, connection_name, project_name, branch, files, dirs=[],
                  precedence=zuul.model.PRECEDENCE_HIGH):
         data = dict(connection=connection_name,
                     project=project_name,
                     branch=branch,
-                    files=files)
+                    files=files,
+                    dirs=dirs)
         job = self.submitJob('merger:cat', data, None, precedence)
         return job
 
diff --git a/zuul/merger/merger.py b/zuul/merger/merger.py
index 2ac0de8..93340fa 100644
--- a/zuul/merger/merger.py
+++ b/zuul/merger/merger.py
@@ -254,7 +254,7 @@
             origin.fetch()
         origin.fetch(tags=True)
 
-    def getFiles(self, files, branch=None, commit=None):
+    def getFiles(self, files, dirs=[], branch=None, commit=None):
         ret = {}
         repo = self.createRepoObject()
         if branch:
@@ -266,6 +266,14 @@
                 ret[fn] = tree[fn].data_stream.read().decode('utf8')
             else:
                 ret[fn] = None
+        if dirs:
+            for dn in dirs:
+                if dn not in tree:
+                    continue
+                for blob in tree[dn].traverse():
+                    if blob.path.endswith(".yaml"):
+                        ret[blob.path] = blob.data_stream.read().decode(
+                            'utf-8')
         return ret
 
     def deleteRemote(self, remote):
@@ -452,7 +460,7 @@
                 return None
         return commit
 
-    def mergeChanges(self, items, files=None, repo_state=None):
+    def mergeChanges(self, items, files=None, dirs=None, repo_state=None):
         # connection+project+branch -> commit
         recent = {}
         commit = None
@@ -470,9 +478,9 @@
             commit = self._mergeItem(item, recent, repo_state)
             if not commit:
                 return None
-            if files:
+            if files or dirs:
                 repo = self.getRepo(item['connection'], item['project'])
-                repo_files = repo.getFiles(files, commit=commit)
+                repo_files = repo.getFiles(files, dirs, commit=commit)
                 read_files.append(dict(
                     connection=item['connection'],
                     project=item['project'],
@@ -483,6 +491,6 @@
             ret_recent[k] = v.hexsha
         return commit.hexsha, read_files, repo_state, ret_recent
 
-    def getFiles(self, connection_name, project_name, branch, files):
+    def getFiles(self, connection_name, project_name, branch, files, dirs=[]):
         repo = self.getRepo(connection_name, project_name)
-        return repo.getFiles(files, branch=branch)
+        return repo.getFiles(files, dirs, branch=branch)
diff --git a/zuul/merger/server.py b/zuul/merger/server.py
index cbc4cb8..555a4bc 100644
--- a/zuul/merger/server.py
+++ b/zuul/merger/server.py
@@ -94,8 +94,9 @@
 
     def merge(self, job):
         args = json.loads(job.arguments)
-        ret = self.merger.mergeChanges(args['items'], args.get('files'),
-                                       args.get('repo_state'))
+        ret = self.merger.mergeChanges(
+            args['items'], args.get('files'),
+            args.get('dirs'), args.get('repo_state'))
         result = dict(merged=(ret is not None),
                       zuul_url=self.zuul_url)
         if ret is None:
@@ -109,7 +110,8 @@
         args = json.loads(job.arguments)
         self.merger.updateRepo(args['connection'], args['project'])
         files = self.merger.getFiles(args['connection'], args['project'],
-                                     args['branch'], args['files'])
+                                     args['branch'], args['files'],
+                                     args.get('dirs'))
         result = dict(updated=True,
                       files=files,
                       zuul_url=self.zuul_url)
diff --git a/zuul/model.py b/zuul/model.py
index 436a9c8..f901c55 100644
--- a/zuul/model.py
+++ b/zuul/model.py
@@ -1848,7 +1848,9 @@
         return set()
 
     def updatesConfig(self):
-        if 'zuul.yaml' in self.files or '.zuul.yaml' in self.files:
+        if 'zuul.yaml' in self.files or '.zuul.yaml' in self.files or \
+           [True for fn in self.files if fn.startswith("zuul.d/") or
+            fn.startswith(".zuul.d/")]:
             return True
         return False