Index: wp-includes/js/media-editor.js
===================================================================
--- wp-includes/js/media-editor.js	(revision 22901)
+++ wp-includes/js/media-editor.js	(working copy)
@@ -533,7 +533,10 @@
 				workflow.open();
 			else
 				workflow = wp.media.editor.add( id );
-
+			
+			// Add focus to modal
+			$( '.media-menu .active' ).focus();
+			
 			return workflow;
 		}
 	};
Index: wp-includes/js/media-views.js
===================================================================
--- wp-includes/js/media-views.js	(revision 22901)
+++ wp-includes/js/media-views.js	(working copy)
@@ -550,6 +550,9 @@
 			this.frame.content.on( 'activate:browse', this.gallerySettings, this );
 
 			media.controller.Library.prototype.activate.apply( this, arguments );
+			
+			// Make sure focus stays on modal
+			$( '.media-menu .active' ).focus();
 		},
 
 		deactivate: function() {
@@ -1491,10 +1494,12 @@
 						text:     l10n.cancelGalleryTitle,
 						priority: 20,
 						click:    function() {
-							if ( previous )
+							if ( previous ) {
 								frame.state( previous );
-							else
+								$( '.media-menu .active' ).focus();
+							} else {
 								frame.close();
+							}
 						}
 					},
 					separateCancel: new media.View({
@@ -1649,7 +1654,8 @@
 		template: media.template('media-modal'),
 
 		events: {
-			'click .media-modal-backdrop, .media-modal-close' : 'closeHandler'
+			'click .media-modal-backdrop, .media-modal-close' : 'closeHandler',
+			'keyup' : 'keyboard'
 		},
 
 		initialize: function() {
@@ -1715,6 +1721,16 @@
 			// Set and render the content.
 			this.options.$content = ( $content instanceof Backbone.View ) ? $content.$el : $content;
 			return this.render();
+		},
+
+		keyboard: function( event ) {
+
+			if ( 27 !== event.which ) // Esc
+				return;
+
+			this.close();
+
+			event.preventDefault();
 		}
 	});
 
@@ -2376,7 +2392,8 @@
 		className: 'media-menu-item',
 
 		events: {
-			'click': 'click'
+			'click': 'click',
+			'keyup': 'keyboard'
 		},
 
 		click: function() {
@@ -2388,7 +2405,19 @@
 				this.controller.state( options.state );
 		},
 
+		keyboard: function( event ) {
+			if ( 13 !== event.which ) // Enter
+				return;
+
+			this.click();
+
+			event.preventDefault();
+		},
+
 		render: function() {
+			
+			this.$el.attr('tabIndex', '0');
+			
 			var options = this.options;
 
 			if ( options.text )
@@ -2417,6 +2446,7 @@
 
 		events: {
 			'click .attachment-preview':      'toggleSelection',
+			'keyup .attachment-preview':      'toggleSelection',
 			'change [data-setting]':          'updateSetting',
 			'change [data-setting] input':    'updateSetting',
 			'change [data-setting] select':   'updateSetting',
@@ -2494,6 +2524,10 @@
 		},
 
 		toggleSelection: function( event ) {
+			
+			if ( event.type === 'keyup' && 13 !== event.which ) // Enter 
+				return;
+			
 			var selection = this.options.selection,
 				model = this.model;
 
Index: wp-includes/media.php
===================================================================
--- wp-includes/media.php	(revision 22901)
+++ wp-includes/media.php	(working copy)
@@ -1603,7 +1603,7 @@
 	</script>
 
 	<script type="text/html" id="tmpl-attachment">
-		<div class="attachment-preview type-{{ data.type }} subtype-{{ data.subtype }} {{ data.orientation }}">
+		<div class="attachment-preview type-{{ data.type }} subtype-{{ data.subtype }} {{ data.orientation }}" tabindex="0">
 			<# if ( data.uploading ) { #>
 				<div class="media-progress-bar"><div></div></div>
 			<# } else if ( 'image' === data.type ) { #>
@@ -1624,7 +1624,7 @@
 			<# } #>
 
 			<# if ( data.buttons.check ) { #>
-				<a class="check" href="#"><span>&#10003;</span><span class="dash">&ndash;</span></a>
+				<a class="check" href="#" tabindex="-1"><span>&#10003;</span><span class="dash">&ndash;</span></a>
 			<# } #>
 		</div>
 		<# if ( data.describe ) { #>
Index: wp-includes/css/media-views.css
===================================================================
--- wp-includes/css/media-views.css	(revision 22901)
+++ wp-includes/css/media-views.css	(working copy)
@@ -386,8 +386,10 @@
 	cursor: pointer;
 }
 
-.media-menu li:hover {
+.media-menu li:hover,
+.media-menu li:focus {
 	background: rgba( 0, 0, 0, 0.04 );
+	outline: none;
 }
 
 .media-menu .active,
@@ -523,6 +525,10 @@
 	cursor: pointer;
 }
 
+.attachment-preview:focus {
+	outline: thin dotted;
+}
+
 .attachment .icon {
 	margin: 0 auto;
 	overflow: hidden;