diff --git a/neutron_lib/placement/constants.py b/neutron_lib/placement/constants.py
new file mode 100644
index 000000000..b1d7f40c1
--- /dev/null
+++ b/neutron_lib/placement/constants.py
@@ -0,0 +1,33 @@
+# Copyright 2018 Ericsson
+#
+# 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.
+
+# trait prefixes to be used after CUSTOM_
+TRAIT_PREFIX_VNIC_TYPE = 'VNIC_TYPE_'
+TRAIT_PREFIX_PHYSNET = 'PHYSNET_'
+
+# resource classes
+CLASS_NET_BW_EGRESS_KBPS = 'NET_BANDWIDTH_EGRESS_KILOBITS_PER_SECOND'
+CLASS_NET_BW_INGRESS_KBPS = 'NET_BANDWIDTH_INGRESS_KILOBITS_PER_SECOND'
+
+# Optionally reported inventory parameters. Mandatory parameters like 'total'
+# are left out intentionally. See also:
+# https://developer.openstack.org/api-ref/placement
+#        /#update-resource-provider-inventory
+INVENTORY_OPTIONS = set([
+    'allocation_ratio',
+    'max_unit',
+    'min_unit',
+    'reserved',
+    'step_size',
+    ])
diff --git a/releasenotes/notes/placement-constants-f2629b98f6fe148f.yaml b/releasenotes/notes/placement-constants-f2629b98f6fe148f.yaml
new file mode 100644
index 000000000..7a240e529
--- /dev/null
+++ b/releasenotes/notes/placement-constants-f2629b98f6fe148f.yaml
@@ -0,0 +1,4 @@
+---
+features:
+  - |
+    New constants module for Placement: ``neutron_lib.placement.constants``.