diff --git a/chrome/content/zotero/overlay.js b/chrome/content/zotero/overlay.js
index 9e3e219fe..d80a18421 100644
--- a/chrome/content/zotero/overlay.js
+++ b/chrome/content/zotero/overlay.js
@@ -36,6 +36,7 @@ var ZoteroPane = new function()
 	this.handleKeyDown = handleKeyDown;
 	this.handleKeyUp = handleKeyUp;
 	this.setHighlightedRowsCallback = setHighlightedRowsCallback;
+	this.handleKeyPress = handleKeyPress;
 	this.newItem = newItem;
 	this.newCollection = newCollection;
 	this.newSearch = newSearch;
@@ -329,6 +330,49 @@ var ZoteroPane = new function()
 	}
 	
 	
+	function handleKeyPress(event, from) {
+		var key = String.fromCharCode(event.which);
+		
+		if (from == 'zotero-collections-tree') {
+			if (event.keyCode == event.DOM_VK_BACK_SPACE ||
+					event.keyCode == event.DOM_VK_DELETE) {
+				ZoteroPane.deleteSelectedCollection();
+				event.preventDefault();
+				return;
+			}
+			
+			if (key == '+' && !(event.ctrlKey || event.altKey || event.metaKey)) {
+				ZoteroPane.collectionsView.expandAllRows();
+				return;
+			}
+			else if (key == '-' && !(event.shiftKey || event.ctrlKey ||
+					event.altKey || event.metaKey)) {
+				ZoteroPane.collectionsView.collapseAllRows();
+				return;
+			}
+		}
+		else if (from == 'zotero-items-tree') {
+			if (event.keyCode == event.DOM_VK_BACK_SPACE ||
+					event.keyCode == event.DOM_VK_DELETE) {
+				ZoteroPane.deleteSelectedItem();
+				event.preventDefault();
+				return;
+			}
+			
+			if (key == '+' && !(event.ctrlKey || event.altKey || event.metaKey)) {
+				ZoteroPane.itemsView.expandAllRows();
+				return;
+			}
+			else if (key == '-' && !(event.shiftKey || event.ctrlKey ||
+					event.altKey || event.metaKey)) {
+				ZoteroPane.itemsView.collapseAllRows();
+				return;
+			}
+		}
+		
+	}
+	
+	
 	/*
 	 * Create a new item
 	 *
diff --git a/chrome/content/zotero/overlay.xul b/chrome/content/zotero/overlay.xul
index cc1c5f34c..e54b3d0d7 100644
--- a/chrome/content/zotero/overlay.xul
+++ b/chrome/content/zotero/overlay.xul
@@ -125,7 +125,7 @@
 						onselect="ZoteroPane.onCollectionSelected();" seltype="single"
 						ondragdrop="nsDragAndDrop.drop(event, ZoteroPane.collectionsView)"
 						ondraggesture="if (event.target.localName == 'treechildren') nsDragAndDrop.startDrag(event, ZoteroPane.collectionsView);"
-						onkeypress="if (event.keyCode == event.DOM_VK_BACK_SPACE || event.keyCode == event.DOM_VK_DELETE){ ZoteroPane.deleteSelectedCollection(); event.preventDefault(); }"
+						onkeypress="ZoteroPane.handleKeyPress(event, this.id)"
 						flex="1">
 						<treecols>
 							<treecol
@@ -183,7 +183,7 @@
 						ondblclick="ZoteroPane.onDoubleClick(event, this);"
 						enableColumnDrag="true"
 						onfocus="if (ZoteroPane.itemsView.rowCount &amp;&amp; !ZoteroPane.itemsView.selection.count) { ZoteroPane.itemsView.selection.select(0); }"
-						onkeypress="if (event.keyCode == event.DOM_VK_BACK_SPACE || event.keyCode == event.DOM_VK_DELETE){ ZoteroPane.deleteSelectedItem(); event.preventDefault(); }"
+						onkeypress="ZoteroPane.handleKeyPress(event, this.id)"
 						onselect="ZoteroPane.itemSelected();"
 						ondraggesture="if (event.target.localName == 'treechildren') nsDragAndDrop.startDrag(event,ZoteroPane.itemsView);"
 						ondragover="nsDragAndDrop.dragOver(event, ZoteroPane.itemsView)"
diff --git a/chrome/content/zotero/xpcom/collectionTreeView.js b/chrome/content/zotero/xpcom/collectionTreeView.js
index 339a00d39..8cdab3f0c 100644
--- a/chrome/content/zotero/xpcom/collectionTreeView.js
+++ b/chrome/content/zotero/xpcom/collectionTreeView.js
@@ -360,6 +360,29 @@ Zotero.CollectionTreeView.prototype.toggleOpenState = function(row)
 	this._refreshHashMap();
 }
 
+
+Zotero.CollectionTreeView.prototype.expandAllRows = function() {
+	this._treebox.beginUpdateBatch();
+	for (var i=0; i<this.rowCount; i++) {
+		if (this.isContainer(i) && !this.isContainerOpen(i)) {
+			this.toggleOpenState(i);
+		}
+	}
+	this._treebox.endUpdateBatch();
+}
+
+
+Zotero.CollectionTreeView.prototype.collapseAllRows = function() {
+	this._treebox.beginUpdateBatch();
+	for (var i=0; i<this.rowCount; i++) {
+		if (this.isContainer(i) && this.isContainerOpen(i)) {
+			this.toggleOpenState(i);
+		}
+	}
+	this._treebox.endUpdateBatch();
+}
+
+
 ////////////////////////////////////////////////////////////////////////////////
 ///
 ///  Additional functions for managing data in the tree
diff --git a/chrome/content/zotero/xpcom/itemTreeView.js b/chrome/content/zotero/xpcom/itemTreeView.js
index e64c58874..1b3754c0b 100644
--- a/chrome/content/zotero/xpcom/itemTreeView.js
+++ b/chrome/content/zotero/xpcom/itemTreeView.js
@@ -475,6 +475,29 @@ Zotero.ItemTreeView.prototype.toggleOpenState = function(row)
 	this._refreshHashMap();
 }
 
+
+Zotero.ItemTreeView.prototype.expandAllRows = function() {
+	this._treebox.beginUpdateBatch();
+	for (var i=0; i<this.rowCount; i++) {
+		if (this.isContainer(i) && !this.isContainerOpen(i)) {
+			this.toggleOpenState(i);
+		}
+	}
+	this._treebox.endUpdateBatch();
+}
+
+
+Zotero.ItemTreeView.prototype.collapseAllRows = function() {
+	this._treebox.beginUpdateBatch();
+	for (var i=0; i<this.rowCount; i++) {
+		if (this.isContainer(i) && this.isContainerOpen(i)) {
+			this.toggleOpenState(i);
+		}
+	}
+	this._treebox.endUpdateBatch();
+}
+
+
 Zotero.ItemTreeView.prototype.isSorted = function()
 {
 	// We sort by the first column if none selected, so return true