diff --git a/README.md b/README.md
index 6040be5..e095aff 100644
--- a/README.md
+++ b/README.md
@@ -116,6 +116,8 @@ The type declarations in this repository include the following specifications (g
 	 - [DeviceOrientation Events](https://w3c.github.io/deviceorientation/)
 	 - [Image Resource](https://w3c.github.io/image-resource/)
 	 - [Long Tasks API](https://w3c.github.io/longtasks/)
+	 - [Region Capture](https://w3c.github.io/mediacapture-region/)
+	 - [Screen Capture](https://w3c.github.io/mediacapture-screen-share/)
 	 - [MediaStream Image Capture](https://w3c.github.io/mediacapture-image/)
 	 - [MediaStream Recording](https://w3c.github.io/mediacapture-record/)
 	 - [Permissions Registry](https://w3c.github.io/permissions-registry/)
diff --git a/index.d.ts b/index.d.ts
index 823f38e..cb16ee5 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -33,6 +33,8 @@
 /// <reference path="./w3c/device-orientation.d.ts" />
 /// <reference path="./w3c/image-resource.d.ts" />
 /// <reference path="./w3c/long-tasks.d.ts" />
+/// <reference path="./w3c/mediacapture-region.d.ts" />
+/// <reference path="./w3c/mediacapture-screen-share.d.ts" />
 /// <reference path="./w3c/mediastream-image-capture-global.d.ts" />
 /// <reference path="./w3c/mediastream-image-capture.d.ts" />
 /// <reference path="./w3c/mediastream-recording.d.ts" />
diff --git a/package.json b/package.json
index 11b1559..d08f12f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "new-javascript",
-	"version": "0.4.5",
+	"version": "0.4.6",
 	"description": "TypeScript type definitions for new JavaScript stuff that isn't yet in TypeScript's standard type definitions",
 	"main": "./index.d.ts",
 	"repository": {
diff --git a/w3c/mediacapture-region.d.ts b/w3c/mediacapture-region.d.ts
new file mode 100644
index 0000000..587ec6d
--- /dev/null
+++ b/w3c/mediacapture-region.d.ts
@@ -0,0 +1,23 @@
+
+// Region Capture
+// Specification: https://w3c.github.io/mediacapture-region/
+// Repository: https://github.com/w3c/mediacapture-region
+
+interface CropTarget { }
+
+declare var CropTarget: {
+	prototype: CropTarget;
+	fromElement(element: Element): Promise<CropTarget>;
+};
+
+interface BrowserCaptureMediaStreamTrack {
+	cropTo(cropTarget?: CropTarget): Promise<void>;
+	clone(): BrowserCaptureMediaStreamTrack;
+}
+
+declare var BrowserCaptureMediaStreamTrack: {
+	prototype: BrowserCaptureMediaStreamTrack;
+};
+
+// intentionally the wrong way round since per lib.dom.d.ts, MediaStream.prototype.getVideoTracks() always returns returns MediaStreamTrack[]
+interface MediaStreamTrack extends BrowserCaptureMediaStreamTrack { }
diff --git a/w3c/mediacapture-screen-share.d.ts b/w3c/mediacapture-screen-share.d.ts
new file mode 100644
index 0000000..4b656f8
--- /dev/null
+++ b/w3c/mediacapture-screen-share.d.ts
@@ -0,0 +1,73 @@
+
+// Screen Capture
+// Specification: https://w3c.github.io/mediacapture-screen-share/
+// Repository: https://github.com/w3c/mediacapture-screen-share
+
+interface DisplayMediaStreamOptions {
+	controller?: CaptureController;
+	selfBrowserSurface?: SelfCapturePreferenceEnum;
+	systemAudio?: SystemAudioPreferenceEnum;
+	surfaceSwitching?: SurfaceSwitchingPreferenceEnum;
+	monitorTypeSurfaces?: MonitorTypeSurfacesEnum;
+}
+
+interface MediaTrackSupportedConstraints {
+	logicalSurface?: boolean;
+	cursor?: boolean;
+	restrictOwnAudio?: boolean;
+	suppressLocalAudioPlayback?: boolean;
+}
+
+interface MediaTrackConstraintSet {
+	logicalSurface?: ConstrainBoolean;
+	cursor?: ConstrainDOMString;
+	restrictOwnAudio?: ConstrainBoolean;
+	suppressLocalAudioPlayback?: ConstrainBoolean;
+}
+
+interface MediaTrackSettings {
+	logicalSurface?: boolean;
+	cursor?: boolean;
+	restrictOwnAudio?: boolean;
+	suppressLocalAudioPlayback?: boolean;
+}
+
+interface MediaTrackCapabilities {
+	logicalSurface?: boolean;
+	cursor?: string[],
+}
+
+interface CaptureController {
+	setFocusBehavior(focusBehavior: CaptureStartFocusBehavior): void;
+}
+
+type CaptureStartFocusBehavior = (
+	| "focus-capturing-application"
+	| "focus-captured-surface"
+	| "no-focus-change"
+);
+
+declare var CaptureController: {
+	prototype: CaptureController;
+	new(): CaptureController;
+}
+
+type SelfCapturePreferenceEnum = (
+	| "include"
+	| "exclude"
+);
+
+type SystemAudioPreferenceEnum = (
+	| "include"
+	| "exclude"
+);
+
+type SurfaceSwitchingPreferenceEnum = (
+	| "include"
+	| "exclude"
+);
+
+type MonitorTypeSurfacesEnum = (
+	| "include"
+	| "exclude"
+);