diff --git a/chrome/content/zotero/overlay.js b/chrome/content/zotero/overlay.js
index 20650d9dd..4e6236ac5 100644
--- a/chrome/content/zotero/overlay.js
+++ b/chrome/content/zotero/overlay.js
@@ -33,7 +33,9 @@ var ZoteroPane = new function()
 	this.onUnload = onUnload;
 	this.toggleDisplay = toggleDisplay;
 	this.fullScreen = fullScreen;
-	this.handleKeyPress = handleKeyPress;
+	this.handleKeyDown = handleKeyDown;
+	this.handleKeyUp = handleKeyUp;
+	this.setHighlightedRowsCallback = setHighlightedRowsCallback;
 	this.newItem = newItem;
 	this.newCollection = newCollection;
 	this.newSearch = newSearch;
@@ -91,6 +93,9 @@ var ZoteroPane = new function()
 			newPane.setAttribute('id','zotero-pane');
 			newPane.setAttribute('persist','height');
 			newPane.setAttribute('hidden', true);
+			newPane.setAttribute('onkeydown', 'ZoteroPane.handleKeyDown(event, this.id)');
+			newPane.setAttribute('onkeyup', 'ZoteroPane.handleKeyUp(event, this.id)');
+			
 			newPane.height = oldPane.height;
 			while(oldPane.hasChildNodes())
 				newPane.appendChild(oldPane.firstChild);
@@ -214,7 +219,33 @@ var ZoteroPane = new function()
 	/*
 	 * Trigger actions based on keyboard shortcuts
 	 */
-	function handleKeyPress(event) {
+	function handleKeyDown(event, from) {
+		if (from == 'zotero-pane') {
+			// Highlight collections containing selected items
+			//
+			// We use Control (17) on Windows because Alt triggers the menubar;
+			// 	otherwise we use Alt/Option (18)
+			if ((Zotero.isWin && event.keyCode == 17 && !event.altKey) ||
+					(!Zotero.isWin && event.keyCode == 18 && !event.ctrlKey)
+					&& !event.shiftKey && !event.metaKey) {
+				
+				this.highlightTimer = Components.classes["@mozilla.org/timer;1"].
+					createInstance(Components.interfaces.nsITimer);
+				// {} implements nsITimerCallback
+				this.highlightTimer.initWithCallback({
+					notify: ZoteroPane.setHighlightedRowsCallback
+				}, 225, Components.interfaces.nsITimer.TYPE_ONE_SHOT);
+			}
+			else if ((Zotero.isWin && event.ctrlKey) ||
+					(!Zotero.isWin && event.altKey)) {
+				if (this.highlightTimer) {
+					this.highlightTimer.cancel();
+					this.highlightTimer = null;
+				}
+				ZoteroPane.collectionsView.setHighlightedRows();
+			}
+		}
+		
 		// Ignore keystrokes if Zotero pane is closed
 		if (document.getElementById('zotero-pane').getAttribute('hidden') == 'true') {
 			return;
@@ -264,13 +295,42 @@ var ZoteroPane = new function()
 				ZoteroPane.fullScreen();
 				break;
 			default:
-				throw ('Command "' + command + '" not found in ZoteroPane.handleKeyPress()');
+				throw ('Command "' + command + '" not found in ZoteroPane.handleKeyDown()');
 		}
 		
 		event.preventDefault();
 	}
 	
 	
+	function handleKeyUp(event, from) {
+		if (from == 'zotero-pane') {
+			if ((Zotero.isWin && event.keyCode == 17) ||
+					(!Zotero.isWin && event.keyCode == 18)) {
+				if (this.highlightTimer) {
+					this.highlightTimer.cancel();
+					this.highlightTimer = null;
+				}
+				ZoteroPane.collectionsView.setHighlightedRows();
+			}
+		}
+	}
+	
+	
+	/*
+	 * Highlights collections containing selected items on Ctrl (Win) or
+	 * Option/Alt (Mac/Linux) press
+	 */
+	function setHighlightedRowsCallback() {
+		var itemIDs = ZoteroPane.getSelectedItems(true);
+		if (itemIDs) {
+			var collectionIDs = Zotero.Collections.getCollectionsContainingItems(itemIDs, true);
+			if (collectionIDs) {
+				ZoteroPane.collectionsView.setHighlightedRows(collectionIDs);
+			}
+		}
+	}
+	
+	
 	/*
 	 * Create a new item
 	 *
diff --git a/chrome/content/zotero/overlay.xul b/chrome/content/zotero/overlay.xul
index 60521a259..f64e8e607 100644
--- a/chrome/content/zotero/overlay.xul
+++ b/chrome/content/zotero/overlay.xul
@@ -66,7 +66,9 @@
 		<!-- onmouseup shouldn't be necessary but seems to help prevent tag selector from sometimes going off the screen -->
 		<splitter id="zotero-splitter" resizebefore="closest" resizeafter="closest" hidden="true"
 			onmouseup="ZoteroPane.updateTagSelectorSize()"/>
-		<hbox id="zotero-pane" persist="height" hidden="true">
+		<hbox id="zotero-pane" persist="height" hidden="true"
+			onkeydown="ZoteroPane.handleKeyDown(event, this.id)"
+			onkeyup="ZoteroPane.handleKeyUp(event, this.id)">
 			<popupset>
 				<popup id="zotero-collectionmenu" onpopupshowing="ZoteroPane.buildCollectionContextMenu();">
 					<menuitem label="&zotero.toolbar.newCollection.label;" oncommand="ZoteroPane.newCollection()"/>
@@ -120,6 +122,7 @@
 						</toolbarbutton>
 					</toolbar>
 					<tree id="zotero-collections-tree" hidecolumnpicker="true" context="zotero-collectionmenu"
+						onmouseover="ZoteroPane.collectionsView.setHighlightedRows();"
 						ondblclick="ZoteroPane.onDoubleClick(event, this);"
 						onselect="ZoteroPane.onCollectionSelected();" seltype="single"
 						ondragdrop="nsDragAndDrop.drop(event, ZoteroPane.collectionsView)"
@@ -339,7 +342,7 @@
 		}
 	}, false);
 	
-	document.getElementById('appcontent').addEventListener('keydown', ZoteroPane.handleKeyPress, true);
+	document.getElementById('appcontent').addEventListener('keydown', ZoteroPane.handleKeyDown, true);
 	</script>
 	
 	<menupopup id="menu_ToolsPopup">
diff --git a/chrome/content/zotero/xpcom/collectionTreeView.js b/chrome/content/zotero/xpcom/collectionTreeView.js
index 413bf95f5..049d91690 100644
--- a/chrome/content/zotero/xpcom/collectionTreeView.js
+++ b/chrome/content/zotero/xpcom/collectionTreeView.js
@@ -36,6 +36,8 @@ Zotero.CollectionTreeView = function()
 	this._treebox = null;
 	this.refresh();
 	
+	this._highlightedRows = {};
+	
 	this._unregisterID = Zotero.Notifier.registerObserver(this, ['collection', 'search']);
 }
 
@@ -212,6 +214,22 @@ Zotero.CollectionTreeView.prototype.notify = function(action, type, ids)
 	}
 }
 
+
+/*
+ * Set the rows that should be highlighted -- actually highlighting is done
+ * by getRowProperties based on the array set here
+ */
+Zotero.CollectionTreeView.prototype.setHighlightedRows = function (ids) {
+	this._highlightedRows = {};
+	this._treebox.invalidate();
+	
+	for each(var id in ids) {
+		this._highlightedRows[this._collectionRowMap[id]] = true;
+		this._treebox.invalidateRow(this._collectionRowMap[id]);
+	}
+}
+
+
 /*
  *  Unregisters view from Zotero.Notifier (called on window close)
  */
@@ -634,7 +652,16 @@ Zotero.CollectionTreeView.prototype.onDrop = function (evt,dropdata,session) { }
 Zotero.CollectionTreeView.prototype.isSorted = function() 							{ return false; }
 Zotero.CollectionTreeView.prototype.isSeparator = function(row) 					{ return false; }
 Zotero.CollectionTreeView.prototype.isEditable = function(row, idx) 				{ return false; }
-Zotero.CollectionTreeView.prototype.getRowProperties = function(row, prop) 		{ }
+
+/* Set 'highlighted' property on rows set by setHighlightedRows */
+Zotero.CollectionTreeView.prototype.getRowProperties = function(row, props) {
+	if (this._highlightedRows[row]) {
+		var aServ = Components.classes["@mozilla.org/atom-service;1"].
+			getService(Components.interfaces.nsIAtomService);
+		props.AppendElement(aServ.getAtom("highlighted"));
+	}
+}
+
 Zotero.CollectionTreeView.prototype.getColumnProperties = function(col, prop) 		{ }
 Zotero.CollectionTreeView.prototype.getCellProperties = function(row, col, prop) 	{ }
 Zotero.CollectionTreeView.prototype.performAction = function(action) 				{ }
diff --git a/chrome/content/zotero/xpcom/data_access.js b/chrome/content/zotero/xpcom/data_access.js
index fb8fb8f17..06e803b82 100644
--- a/chrome/content/zotero/xpcom/data_access.js
+++ b/chrome/content/zotero/xpcom/data_access.js
@@ -3021,6 +3021,7 @@ Zotero.Collections = new function(){
 	
 	this.get = get;
 	this.add = add;
+	this.getCollectionsContainingItems = getCollectionsContainingItems;
 	this.reloadAll = reloadAll;
 	this.unload = unload;
 	
@@ -3073,6 +3074,26 @@ Zotero.Collections = new function(){
 	}
 	
 	
+	function getCollectionsContainingItems(itemIDs, asIDs) {
+		var sql = "SELECT collectionID FROM collections WHERE ";
+		var sqlParams = [];
+		for each(var id in itemIDs) {
+			sql += "collectionID IN (SELECT collectionID FROM collectionItems "
+				+ "WHERE itemID=?) AND "
+			sqlParams.push(id);
+		}
+		sql = sql.substring(0, sql.length - 5);
+		var collectionIDs = Zotero.DB.columnQuery(sql, sqlParams);
+		
+		if (asIDs) {
+			return collectionIDs;
+		}
+		
+		return Zotero.Collections.get(collectionIDs);
+	}
+	
+	
+	
 	/**
 	* Clear collection from internal cache (used by Zotero.Collection.erase())
 	*
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
index 3d35562a0..d6cb34cff 100644
--- a/chrome/content/zotero/xpcom/zotero.js
+++ b/chrome/content/zotero/xpcom/zotero.js
@@ -65,6 +65,7 @@ var Zotero = new function(){
 	this.platform;
 	this.locale;
 	this.isMac;
+	this.isWin;
 	
 	/*
 	 * Initialize the extension
@@ -106,6 +107,7 @@ var Zotero = new function(){
 			   .hiddenDOMWindow;
 		this.platform = win.navigator.platform;
 		this.isMac = (this.platform.substr(0, 3) == "Mac");
+		this.isWin = (this.platform.substr(0, 3) == "Win");
 		
 		// Locale		
 		var localeService = Components.classes['@mozilla.org/intl/nslocaleservice;1'].
diff --git a/chrome/skin/default/zotero/overlay.css b/chrome/skin/default/zotero/overlay.css
index d75cd5e73..75412bf7c 100644
--- a/chrome/skin/default/zotero/overlay.css
+++ b/chrome/skin/default/zotero/overlay.css
@@ -64,6 +64,12 @@
 	margin-right: 5px;
 }
 
+/* Set by setHighlightedRows() and getCellProperties() in collectionTreeView.js) */
+#zotero-collections-tree treechildren::-moz-tree-row(highlighted)
+{
+	background: #FFFF99;
+}
+
 
 #zotero-pane splitter
 {