diff --git a/plejd/DeviceRegistry.js b/plejd/DeviceRegistry.js
new file mode 100644
index 0000000..1a26df4
--- /dev/null
+++ b/plejd/DeviceRegistry.js
@@ -0,0 +1,73 @@
+class DeviceRegistry {
+  apiSite;
+  cryptoKey = null;
+
+  deviceIdsByRoom = {};
+  deviceIdsBySerial = {};
+
+  // Dictionaries of [id]: device per type
+  plejdDevices = {};
+  roomDevices = {};
+  sceneDevices = {};
+
+  get allDevices() {
+    return [
+      ...Object.values(this.plejdDevices),
+      ...Object.values(this.roomDevices),
+      ...Object.values(this.sceneDevices),
+    ];
+  }
+
+  addPlejdDevice(device) {
+    this.plejdDevices[device.id] = device;
+    this.deviceIdsBySerial[device.serialNumber] = device.id;
+    if (!this.deviceIdsByRoom[device.roomId]) {
+      this.deviceIdsByRoom[device.roomId] = [];
+    }
+    this.deviceIdsByRoom[device.roomId].push(device.id);
+  }
+
+  addScene(scene) {
+    this.plejdDevices[scene.id] = scene;
+  }
+
+  setApiSite(siteDetails) {
+    this.apiSite = siteDetails;
+  }
+
+  clearPlejdDevices() {
+    this.plejdDevices = {};
+    this.deviceIdsByRoom = {};
+    this.deviceIdsBySerial = {};
+  }
+
+  addRoomDevice(device) {
+    this.roomDevices[device.id] = device;
+  }
+
+  clearRoomDevices() {
+    this.roomDevices = {};
+  }
+
+  clearSceneDevices() {
+    this.sceneDevices = {};
+  }
+
+  getDevice(deviceId) {
+    return this.plejdDevices[deviceId];
+  }
+
+  getDeviceBySerialNumber(serialNumber) {
+    return this.plejdDevices[this.deviceIdsBySerial[serialNumber]];
+  }
+
+  getDeviceName(deviceId) {
+    return (this.plejdDevices[deviceId] || {}).name;
+  }
+
+  getSceneName(sceneId) {
+    return (this.sceneDevices[sceneId] || {}).name;
+  }
+}
+
+module.exports = DeviceRegistry;