Index: src/wp-includes/js/media-grid.js
===================================================================
--- src/wp-includes/js/media-grid.js	(revision 29023)
+++ src/wp-includes/js/media-grid.js	(working copy)
@@ -213,45 +213,16 @@
 
 			// Handle a frame-level event for editing an attachment.
 			this.on( 'edit:attachment', this.editAttachment, this );
-			this.on( 'edit:attachment:next', this.editNextAttachment, this );
-			this.on( 'edit:attachment:previous', this.editPreviousAttachment, this );
 		},
 
-		editPreviousAttachment: function( currentModel ) {
-			var library = this.state().get('library'),
-				currentModelIndex = library.indexOf( currentModel );
-			this.trigger( 'edit:attachment', library.at( currentModelIndex - 1 ) );
-		},
-
-		editNextAttachment: function( currentModel ) {
-			var library = this.state().get('library'),
-				currentModelIndex = library.indexOf( currentModel );
-			this.trigger( 'edit:attachment', library.at( currentModelIndex + 1 ) );
-		},
-
 		/**
 		 * Open the Edit Attachment modal.
 		 */
 		editAttachment: function( model ) {
-			var library = this.state().get('library'), hasPrevious, hasNext;
-			if ( library.indexOf( model ) > 0 ) {
-				hasPrevious = true;
-			}
-			else {
-				hasPrevious = false;
-			}
-			if ( library.indexOf( model ) < library.length - 1 ) {
-				hasNext = true;
-			}
-			else {
-				hasNext = false;
-			}
-
-			new media.view.Frame.EditAttachment({
-				hasPrevious:    hasPrevious,
-				hasNext:        hasNext,
-				model:          model,
-				gridController: this
+			// Create a new EditAttachment frame, passing along the library.
+			this.editAttachmentFrame = new media.view.Frame.EditAttachments({
+				library: this.state().get('library'),
+				model: model
 			});
 		},
 
@@ -330,7 +301,7 @@
 	 *
 	 * Requires an attachment model to be passed in the options hash under `model`.
 	 */
-	media.view.Frame.EditAttachment = media.view.Frame.extend({
+	media.view.Frame.EditAttachments = media.view.Frame.extend({
 
 		className: 'edit-attachment-frame',
 		template: media.template( 'edit-attachment-frame' ),
@@ -352,6 +323,13 @@
 				state: 'edit-attachment'
 			});
 
+			this.library = this.options.library;
+			if ( this.options.model ) {
+				this.model = this.options.model;
+			} else {
+				this.model = this.library.at( 0 );
+			}
+
 			this.createStates();
 
 			this.on( 'content:render:edit-metadata', this.editMetadataContent, this );
@@ -464,14 +442,27 @@
 			});
 		},
 
+		getCurrentIndex: function() {
+			return this.library.indexOf( this.model );
+		},
+
+		hasNext: function() {
+			return ( this.getCurrentIndex() + 1 ) < this.library.length;
+		},
+
+		hasPrevious: function() {
+			return ( this.getCurrentIndex() - 1 ) > -1;
+		},
+
 		/**
 		 * Click handler to switch to the previous media item.
 		 */
 		previousMediaItem: function() {
-			if ( ! this.options.hasPrevious )
+			if ( ! this.hasPrevious() ) {
 				return;
-			this.modal.close();
-			this.options.gridController.trigger( 'edit:attachment:previous', this.model );
+			}
+			this.model = this.library.at( this.getCurrentIndex() - 1 );
+			this.editMetadataContent();
 		},
 
 		/**
@@ -478,12 +469,12 @@
 		 * Click handler to switch to the next media item.
 		 */
 		nextMediaItem: function() {
-			if ( ! this.options.hasNext )
+			if ( ! this.hasNext() ) {
 				return;
-			this.modal.close();
-			this.options.gridController.trigger( 'edit:attachment:next', this.model );
+			}
+			this.model = this.library.at( this.getCurrentIndex() + 1 );
+			this.editMetadataContent();
 		}
-
 	});
 
 	media.view.GridFieldOptions = media.View.extend({