diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/l2monitoring/cfm/service/MdStore.java b/incubator/api/src/main/java/org/onosproject/incubator/net/l2monitoring/cfm/service/MdStore.java
new file mode 100644
index 0000000..26a3933
--- /dev/null
+++ b/incubator/api/src/main/java/org/onosproject/incubator/net/l2monitoring/cfm/service/MdStore.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2017-present Open Networking Foundation
+ *
+ * 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.
+ */
+package org.onosproject.incubator.net.l2monitoring.cfm.service;
+
+import org.onosproject.incubator.net.l2monitoring.cfm.MaintenanceDomain;
+import org.onosproject.incubator.net.l2monitoring.cfm.identifier.MdId;
+import org.onosproject.store.Store;
+
+import java.util.Collection;
+import java.util.Optional;
+
+/**
+ * {@link org.onosproject.incubator.net.l2monitoring.cfm.MaintenanceDomain Maintenance Domain's} storage interface.
+ * Note: because the MaintenanceDomain is immutable if anything needs to be
+ * changed in it, then it must be replaced in the store. This includes adding
+ * and deleting Maintenance Associations from an MD.
+ */
+public interface MdStore extends Store<MdEvent, MdStoreDelegate> {
+    /**
+     * Get a list of all of the Maintenance Domains on the system.
+     * @return A collection Maintenance domains from the MD Store.
+     */
+    Collection<MaintenanceDomain> getAllMaintenanceDomain();
+
+    /**
+     * Get a specific Maintenance Domain by its identifier.
+     * @param mdName An identifier for the Maintenance Domain
+     * @return A Maintenance Domain from the MD Store. Empty if not found.
+     */
+    Optional<MaintenanceDomain> getMaintenanceDomain(MdId mdName);
+
+    /**
+     * Delete a specific Maintenance Domain by its identifier.
+     * @param mdName An identifier for the Maintenance Domain to be deleted
+     * @return True if the MD was found and deleted
+     */
+    boolean deleteMaintenanceDomain(MdId mdName);
+
+    /**
+     * Create or replace a Maintenance Domain.
+     * @param md The Maintenance Domain to create or replace
+     * @return true if an MD of this name already existed
+     */
+    boolean createUpdateMaintenanceDomain(MaintenanceDomain md);
+}