diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiSharedTopologyModel.java b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiSharedTopologyModel.java
new file mode 100644
index 0000000..1e1374a
--- /dev/null
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiSharedTopologyModel.java
@@ -0,0 +1,59 @@
+/*
+ *  Copyright 2016 Open Networking Laboratory
+ *
+ *  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.ui.impl.topo.model;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A lazily-initialized Singleton that creates and maintains the UI-model
+ * of the network topology.
+ */
+public final class UiSharedTopologyModel {
+
+    private static final Logger log =
+            LoggerFactory.getLogger(UiSharedTopologyModel.class);
+
+    private static UiSharedTopologyModel singleton = null;
+
+    private UiSharedTopologyModel() {
+        // TODO: set up core model listeners and build the state of the model
+    }
+
+    public void register(UiTopoLayout layout) {
+        log.info("Registering topology layout {}", layout);
+        // TODO: register the view
+    }
+
+    public void unregister(UiTopoLayout layout) {
+        log.info("Unregistering topology layout {}", layout);
+        // TODO: unregister the view
+    }
+
+    /**
+     * Returns a reference to the Singleton UI network topology model.
+     *
+     * @return the singleton topology model
+     */
+    public static synchronized UiSharedTopologyModel instance() {
+        if (singleton == null) {
+            log.info("Instantiating Singleton.");
+            singleton = new UiSharedTopologyModel();
+        }
+        return singleton;
+    }
+}
diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiTopoLayout.java b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiTopoLayout.java
new file mode 100644
index 0000000..b71b81e
--- /dev/null
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiTopoLayout.java
@@ -0,0 +1,72 @@
+/*
+ *  Copyright 2016 Open Networking Laboratory
+ *
+ *  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.ui.impl.topo.model;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Base class for modeling the Topology View layout.
+ * <p>
+ * Note that an instance of this class will be created for each
+ * {@link org.onosproject.ui.impl.UiWebSocket} connection, and will contain
+ * the state of how the topology is laid out for the logged-in user.
+ */
+public class UiTopoLayout {
+    private final Logger log = LoggerFactory.getLogger(getClass());
+
+    private final String username;
+    private final UiSharedTopologyModel sharedModel;
+
+    private boolean registered = false;
+
+    /**
+     * Creates a new topology layout.
+     */
+    public UiTopoLayout(String username) {
+        this.username = username;
+        this.sharedModel = UiSharedTopologyModel.instance();
+    }
+
+    /**
+     * Initializes the layout; registering with the shared model.
+     */
+    public void init() {
+        if (!registered) {
+            sharedModel.register(this);
+            registered = true;
+        } else {
+            log.warn("already registered");
+        }
+    }
+
+    /**
+     * Destroys the layout; unregistering from the shared model.
+     */
+    public void destroy() {
+        if (!registered) {
+            sharedModel.unregister(this);
+        } else {
+            log.warn("already unregistered");
+        }
+    }
+
+    @Override
+    public String toString() {
+        return String.format("{UiTopoLayout for user <%s>}", username);
+    }
+}
diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/package-info.java b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/package-info.java
new file mode 100644
index 0000000..b0cbf54
--- /dev/null
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/package-info.java
@@ -0,0 +1,20 @@
+/*
+ *  Copyright 2016 Open Networking Laboratory
+ *
+ *  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.
+ */
+
+/**
+ * Server-side modeling of the Topology View.
+ */
+package org.onosproject.ui.impl.topo.model;