diff --git a/src/foundry/foundry.js/avClient.d.ts b/src/foundry/foundry.js/avClient.d.ts
index 0c19374f4..452f85d35 100644
--- a/src/foundry/foundry.js/avClient.d.ts
+++ b/src/foundry/foundry.js/avClient.d.ts
@@ -1,5 +1,5 @@
 /**
- * An implementation interface for an Audio/Video client which is extended to provide broadcasting functionality.
+ * An interface for an Audio/Video client which is extended to provide broadcasting functionality.
  */
 declare abstract class AVClient {
   /**
@@ -8,10 +8,36 @@ declare abstract class AVClient {
    */
   constructor(master: AVMaster, settings: AVSettings);
 
+  /**
+   * The master orchestration instance
+   */
   master: AVMaster;
 
+  /**
+   * The active audio/video settings being used
+   */
   settings: AVSettings;
 
+  /**
+   * Is audio broadcasting push-to-talk enabled?
+   */
+  get isVoicePTT(): boolean;
+
+  /**
+   * Is audio broadcasting always enabled?
+   */
+  get isVoiceAlways(): boolean;
+
+  /**
+   * Is audio broadcasting voice-activation enabled?
+   */
+  get isVoiceActivated(): boolean;
+
+  /**
+   * Is the current user muted?
+   */
+  get isMuted(): boolean;
+
   /**
    * One-time initialization actions that should be performed for this client implementation.
    * This will be called only once when the Game object is first set-up.
@@ -37,19 +63,26 @@ declare abstract class AVClient {
    * Provide an Object of available audio sources which can be used by this implementation.
    * Each object key should be a device id and the key should be a human-readable label.
    */
-  abstract getAudioSinks(): Promise<Record<string, string>>;
+  getAudioSinks(): Promise<Record<string, string>>;
 
   /**
    * Provide an Object of available audio sources which can be used by this implementation.
    * Each object key should be a device id and the key should be a human-readable label.
    */
-  abstract getAudioSources(): Promise<Record<string, string>>;
+  getAudioSources(): Promise<Record<string, string>>;
 
   /**
    * Provide an Object of available video sources which can be used by this implementation.
    * Each object key should be a device id and the key should be a human-readable label.
    */
-  abstract getVideoSources(): Promise<Record<string, string>>;
+  getVideoSources(): Promise<Record<string, string>>;
+
+  /**
+   * Obtain a mapping of available device sources for a given type.
+   * @param kind - The type of device source being requested
+   * @internal
+   */
+  _getSourcesOfType(kind: MediaDeviceKind): Promise<Record<string, string>>;
 
   /**
    * Return an array of Foundry User IDs which are currently connected to A/V.
@@ -63,7 +96,7 @@ declare abstract class AVClient {
    * @param userId - The User id
    * @returns The MediaStream for the user, or null if the user does not have one
    */
-  abstract getMediaStreamForUser(userId: string): MediaStream | null;
+  abstract getMediaStreamForUser(userId: string): MediaStream | null | undefined;
 
   /**
    * Is outbound audio enabled for the current user?
diff --git a/src/foundry/foundry.js/avClients/easyRTCClient.d.ts b/src/foundry/foundry.js/avClients/easyRTCClient.d.ts
index 478ba4a8f..3e252c364 100644
--- a/src/foundry/foundry.js/avClients/easyRTCClient.d.ts
+++ b/src/foundry/foundry.js/avClients/easyRTCClient.d.ts
@@ -1,6 +1,12 @@
 /**
  * An AVClient implementation that uses WebRTC and the EasyRTC library.
- */
+ * This client is deprecated and will be removed entirely in 0.9.x.
+ *
+ * If you wish to continue using it, you will need to manually enable it by:
+ * 1. Include the easyrtc.js library which is no longer served
+ * 2. Set CONFIG.WebRTC.clientClass = EasyRTCClient
+ *
+ * @deprecated since 0.8.7 */
 declare class EasyRTCClient extends AVClient {
   /**
    * @param master   - The master orchestration instance
diff --git a/src/foundry/foundry.js/avClients/index.d.ts b/src/foundry/foundry.js/avClients/index.d.ts
new file mode 100644
index 000000000..b6f902d2e
--- /dev/null
+++ b/src/foundry/foundry.js/avClients/index.d.ts
@@ -0,0 +1,2 @@
+import './easyRTCClient';
+import './simplePeerAVClient';
diff --git a/src/foundry/foundry.js/avClients/simplePeerAVClient.d.ts b/src/foundry/foundry.js/avClients/simplePeerAVClient.d.ts
new file mode 100644
index 000000000..b7c5c55ee
--- /dev/null
+++ b/src/foundry/foundry.js/avClients/simplePeerAVClient.d.ts
@@ -0,0 +1,138 @@
+/**
+ * An implementation of the AVClient which uses the simple-peer library and the Foundry socket server for signaling.
+ * Credit to bekit#4213 for identifying simple-peer as a viable technology and providing a POC implementation.
+ */
+declare class SimplePeerAVClient extends AVClient {
+  /**
+   * The local Stream which captures input video and audio
+   * @defaultValue `null`
+   */
+  localStream: MediaStream | null;
+
+  /**
+   * A mapping of connected peers
+   */
+  peers: Map<string, SimplePeer.Instance>;
+
+  /**
+   * A mapping of connected remote streams
+   */
+  remoteStreams: Map<string, MediaStream>;
+
+  /**
+   * Has the client been successfully initialized?
+   * @defaultValue `false`
+   * @internal
+   */
+  _initialized: boolean;
+
+  /**
+   * Is outbound broadcast of local audio enabled?
+   * @defaultValue `false`
+   */
+  audioBroadcastEnabled: boolean;
+
+  /** @override */
+  connect(): Promise<boolean>;
+
+  /** @override */
+  disconnect(): Promise<boolean>;
+
+  /** @override */
+  initialize(): Promise<void>;
+
+  /** @override */
+  getConnectedUsers(): string[];
+
+  /** @override */
+  getMediaStreamForUser(userId: string): MediaStream | null | undefined;
+
+  /** @override */
+  isAudioEnabled(): boolean;
+
+  /** @override */
+  isVideoEnabled(): boolean;
+
+  /** @override */
+  toggleAudio(enable: boolean): void;
+
+  /** @override */
+  toggleBroadcast(broadcast: boolean): void;
+
+  /** @override */
+  toggleVideo(enable: boolean): void;
+
+  /** @override */
+  setUserVideo(userId: string, videoElement: HTMLVideoElement): Promise<void>;
+
+  /**
+   * Initialize a local media stream for the current user
+   */
+  initializeLocalStream(): Promise<MediaStream | null>;
+
+  /**
+   * Listen for Audio/Video updates on the av socket to broker connections between peers
+   */
+  activateSocketListeners(): void;
+
+  /**
+   * Initialize a stream connection with a new peer
+   * @param userId - The Foundry user ID for which the peer stream should be established
+   * @returns A Promise which resolves once the peer stream is initialized
+   */
+  initializePeerStream(userId: string): Promise<SimplePeer.Instance>;
+
+  /**
+   * Receive a request to establish a peer signal with some other User id
+   * @param userId - The Foundry user ID who is requesting to establish a connection
+   * @param data   - The connection details provided by SimplePeer
+   */
+  receiveSignal(userId: string, data: SimplePeer.SignalData): void;
+
+  /**
+   * Connect to a peer directly, either as the initiator or as the receiver
+   * @param userId      - The Foundry user ID with whom we are connecting
+   * @param isInitiator - Is the current user initiating the connection, or responding to it?
+   *                      (default: `false`)
+   * @returns The constructed and configured SimplePeer instance
+   */
+  connectPeer(userId: string, isInitiator?: boolean): SimplePeer.Instance;
+
+  /**
+   * Create the SimplePeer instance for the desired peer connection.
+   * Modules may implement more advanced connection strategies by overriding this method.
+   * @param userId      - The Foundry user ID with whom we are connecting
+   * @param isInitiator - Is the current user initiating the connection, or responding to it?
+   * @internal
+   */
+  _createPeerConnection(userId: string, isInitiator: boolean): SimplePeer.Instance;
+
+  /**
+   * Setup the custom TURN relay to be used in subsequent calls if there is one configured.
+   * TURN credentials are mandatory in WebRTC.
+   * @param options - The SimplePeer configuration object.
+   * @internal
+   */
+  _setupCustomTURN(options: SimplePeer.Options): void;
+
+  /**
+   * Disconnect from a peer by stopping current stream tracks and destroying the SimplePeer instance
+   * @param userId - The Foundry user ID from whom we are disconnecting
+   * @returns A Promise which resolves once the disconnection is complete
+   */
+  disconnectPeer(userId: string): Promise<void>;
+
+  /**
+   * Disconnect from all current peer streams
+   * @returns A Promise which resolves once all peers have been disconnected
+   */
+  disconnectAll(): Promise<Array<void>>;
+
+  /** @override */
+  onSettingsChanged(changed: DeepPartial<AVSettings.Settings>): Promise<void>;
+
+  /**
+   * Replace the local stream for each connected peer with a re-generated MediaStream
+   */
+  updateLocalStream(): Promise<void>;
+}
diff --git a/src/foundry/foundry.js/avMaster.d.ts b/src/foundry/foundry.js/avMaster.d.ts
index 7c691f846..4e3a521f6 100644
--- a/src/foundry/foundry.js/avMaster.d.ts
+++ b/src/foundry/foundry.js/avMaster.d.ts
@@ -12,7 +12,7 @@ declare class AVMaster {
   /**
    * The Audio/Video client class
    */
-  client: AVClient;
+  client: InstanceType<CONFIG['WebRTC']['clientClass']>;
 
   /**
    * A flag to track whether the current user is actively broadcasting their microphone.
diff --git a/src/foundry/foundry.js/avSettings.d.ts b/src/foundry/foundry.js/avSettings.d.ts
index 6937e4e05..bb24b7f34 100644
--- a/src/foundry/foundry.js/avSettings.d.ts
+++ b/src/foundry/foundry.js/avSettings.d.ts
@@ -21,11 +21,7 @@ declare class AVSettings {
     AUDIO_VIDEO: 3;
   };
 
-  static VOICE_MODES: {
-    ALWAYS: 'always';
-    ACTIVITY: 'activity';
-    PTT: 'ptt';
-  };
+  static VOICE_MODES: AVSettings.VoiceModes;
 
   static DEFAULT_CLIENT_SETTINGS: {
     /**
@@ -244,5 +240,13 @@ declare namespace AVSettings {
   type StoredUserSettings = typeof AVSettings.DEFAULT_USER_SETTINGS;
   type UserSettings = StoredUserSettings & { canBroadCastAudio: boolean; canBroadcastVideo: boolean };
   type Settings = { client: ClientSettings; world: WorldSettings };
-  type VoiceMode = ValueOf<typeof AVSettings.VOICE_MODES>;
+  interface DefaultVoiceModes {
+    ALWAYS: 'always';
+    ACTIVITY: 'activity';
+    PTT: 'ptt';
+  }
+  // eslint-disable-next-line @typescript-eslint/no-empty-interface
+  interface Overrides {}
+  type VoiceModes = PropertyTypeOrFallback<AVSettings.Overrides, 'VoiceModes', DefaultVoiceModes>;
+  type VoiceMode = ValueOf<VoiceModes>;
 }
diff --git a/src/foundry/foundry.js/config.d.ts b/src/foundry/foundry.js/config.d.ts
index 9dfe98899..8b9f36ca1 100644
--- a/src/foundry/foundry.js/config.d.ts
+++ b/src/foundry/foundry.js/config.d.ts
@@ -125,6 +125,9 @@ declare global {
   // eslint-disable-next-line @typescript-eslint/no-empty-interface
   interface FlagConfig {}
 
+  // eslint-disable-next-line @typescript-eslint/no-empty-interface
+  interface WebRTCConfig {}
+
   /**
    * Runtime configuration settings for Foundry VTT which exposes a large number of variables which determine how
    * aspects of the software behaves.
@@ -1803,7 +1806,7 @@ declare global {
       /**
        * @defaultValue `SimplePeerAVClient`
        */
-      clientClass: ConstructorOf<AVClient>;
+      clientClass: PropertyTypeOrFallback<WebRTCConfig, 'clientClass', typeof AVClient>;
 
       /**
        * @defaultValue `50`
diff --git a/src/foundry/index.d.ts b/src/foundry/index.d.ts
index ada2db88c..7d128cf56 100644
--- a/src/foundry/index.d.ts
+++ b/src/foundry/index.d.ts
@@ -53,7 +53,7 @@ import './foundry.js/videoHelper';
 
 import './foundry.js/applications';
 
-import './foundry.js/avClients/easyRTCClient';
+import './foundry.js/avClients';
 
 import './foundry.js/clientDocuments/activeEffect';
 import './foundry.js/clientDocuments/actor';
diff --git a/src/types/augments/simple-peer.d.ts b/src/types/augments/simple-peer.d.ts
index 3d07ec791..4b40e3140 100644
--- a/src/types/augments/simple-peer.d.ts
+++ b/src/types/augments/simple-peer.d.ts
@@ -1,3 +1,13 @@
-import * as SimplePeer from 'simple-peer';
-export = SimplePeer;
-export as namespace SimplePeer;
+import * as _SimplePeer from 'simple-peer';
+
+declare global {
+  namespace SimplePeer {
+    type Options = _SimplePeer.Options;
+    type SimplePeer = _SimplePeer.SimplePeer;
+    type TypedArray = _SimplePeer.TypedArray;
+    type SimplePeerData = _SimplePeer.SimplePeerData;
+    type SignalData = _SimplePeer.SignalData;
+    type Instance = _SimplePeer.Instance;
+  }
+  const SimplePeer: SimplePeer.SimplePeer;
+}
diff --git a/src/types/utils.d.ts b/src/types/utils.d.ts
index 9896093fb..9247edb3a 100644
--- a/src/types/utils.d.ts
+++ b/src/types/utils.d.ts
@@ -126,3 +126,5 @@ type StoredDocument<D extends foundry.abstract.Document<any, any>> = D & {
 };
 
 type TemporaryDocument<D> = D extends StoredDocument<infer U> ? U : D;
+
+type PropertyTypeOrFallback<T, Key extends string, Fallback> = Key extends keyof T ? T[Key] : Fallback;
diff --git a/test-d/foundry/avSettings.test-d.ts b/test-d/foundry/avSettings.test-d.ts
new file mode 100644
index 000000000..0a6be8b66
--- /dev/null
+++ b/test-d/foundry/avSettings.test-d.ts
@@ -0,0 +1,23 @@
+import { expectType } from 'tsd';
+
+interface CustomVoiceModes {
+  SOME_CUSTOM_MODE: 'custom';
+}
+
+declare global {
+  // eslint-disable-next-line @typescript-eslint/no-namespace
+  namespace AVSettings {
+    interface Overrides {
+      VoiceModes: CustomVoiceModes;
+    }
+  }
+}
+
+AVSettings.VOICE_MODES = {
+  SOME_CUSTOM_MODE: 'custom'
+};
+
+expectType<CustomVoiceModes>(AVSettings.VOICE_MODES);
+
+const avMaster = new AVMaster();
+expectType<'custom'>(avMaster.mode);
diff --git a/test-d/foundry/foundry.js/avMaster.test-d.ts b/test-d/foundry/foundry.js/avMaster.test-d.ts
new file mode 100644
index 000000000..a603e423c
--- /dev/null
+++ b/test-d/foundry/foundry.js/avMaster.test-d.ts
@@ -0,0 +1,32 @@
+import { expectType } from 'tsd';
+
+declare class CustomAVCLient extends AVClient {
+  initialize(): Promise<void>;
+  connect(): Promise<boolean>;
+  disconnect(): Promise<boolean>;
+  getConnectedUsers(): string[];
+  getMediaStreamForUser(userId: string): MediaStream | null;
+  isAudioEnabled(): boolean;
+  isVideoEnabled(): boolean;
+  toggleAudio(enable: boolean): void;
+  toggleBroadcast(broadcast: boolean): void;
+  toggleVideo(enable: boolean): void;
+  setUserVideo(userId: string, videoElement: HTMLVideoElement): Promise<void>;
+
+  customProperty: string;
+}
+
+declare global {
+  interface WebRTCConfig {
+    clientClass: typeof CustomAVCLient;
+  }
+}
+
+CONFIG.WebRTC.clientClass = CustomAVCLient;
+
+const avMaster = new AVMaster();
+
+expectType<string>(avMaster.client.customProperty);
+if (game instanceof Game) {
+  expectType<string | undefined>(game?.webrtc?.client.customProperty);
+}