diff --git a/ui/bookmarks.js b/ui/bookmarks.js
index 45551f1b..f6d2aee9 100755
--- a/ui/bookmarks.js
+++ b/ui/bookmarks.js
@@ -78,12 +78,15 @@ var toggleBookmark = makeMarkToggler(
 			// add a bookmark...
 			if(action == 'on'){
 				if(BOOKMARKS.indexOf(gid) == -1){
+					/*
 					BOOKMARKS.push(gid)
 					// XXX is this too expensive???
 					// 		...a way to avoid sorting is to:
 					// 			BOOKMARKS.splice(
 					// 				getGIDBefore(gid, BOOKMARKS)+1, 0, gid)
 					BOOKMARKS.sort(imageOrderCmp)
+					*/
+					insertGIDToPosition(gid, BOOKMARKS)
 				}
 
 			// remove a bookmark...
diff --git a/ui/data.js b/ui/data.js
index 993e1ada..f495b09d 100755
--- a/ui/data.js
+++ b/ui/data.js
@@ -600,6 +600,30 @@ function getGIDOrder(gid){
 }
 
 
+// Insert gid to it's position on list...
+//
+// This saves us from very expensive large list sorting via imageOrderCmp
+//
+// These are equivalent:
+//
+// 		insertGIDToPosition(gid, MARKED)
+//
+// 	and
+//
+// 		MARKED.push(gid)
+// 		MARKED.sort(imageOrderCmp)
+//
+// NOTE: this positions the element via DATA.order.
+function insertGIDToPosition(gid, lst, data){
+	data = data == null ? DATA : data
+	gid = gid == null ? getImageGID() : gid
+	var i = lst.indexOf(getGIDBefore(gid, lst, data))
+	i = i == null ? 0 : i+1
+	lst.splice(i, 0, gid)
+	return i
+}
+
+
 // Same as getImageBefore(...), but uses gids and searches in DATA...
 //
 // Return:
@@ -608,7 +632,7 @@ function getGIDOrder(gid){
 //
 // NOTE: if gid is present in the searched ribbon this will return it.
 // NOTE: this uses it's own predicate...
-function getGIDBefore(gid, ribbon, search, data){
+function getGIDBefore(gid, ribbon, data, search){
 	gid = gid == null ? getImageGID() : gid
 	data = data == null ? DATA : data
 	// XXX get a ribbon without getting into DOM...
@@ -791,7 +815,7 @@ function getGIDsAround(count, gid, ribbon, data, force_count){
 
 	var ribbon_data = data.ribbons[ribbon]
 	// get a gid that's in the current ribbon...
-	gid = ribbon_data.indexOf(gid) < 0 ? getGIDBefore(gid, ribbon, null, data) : gid
+	gid = ribbon_data.indexOf(gid) < 0 ? getGIDBefore(gid, ribbon, data) : gid
 
 	// calculate the bounds...
 	var i = ribbon_data.indexOf(gid)
@@ -1329,7 +1353,7 @@ function splitData(data, gid1){
 		// XXX revise...
 		for(var j=0; j<gids.length; j++){
 			var prev = cur
-			var gid = getGIDBefore(gids[j], i, null, data)
+			var gid = getGIDBefore(gids[j], i, data)
 			if(gid == gids[j]){
 				var cur = r.indexOf(gid)
 			} else {
@@ -1686,7 +1710,7 @@ function loadImagesAround(count, gid, ribbon, data, force_count){
 	ribbon = typeof(ribbon) != typeof(123) ? getRibbonIndex(ribbon) : ribbon
 	count = count == null ? Math.round(CONFIG.load_screens * getScreenWidthInImages()) : count
 	// get a gid that exists in the current ribbon...
-	gid = getGIDBefore(gid, ribbon, null, data)
+	gid = getGIDBefore(gid, ribbon, data)
 
 	var ribbon_elem = getRibbon(ribbon)
 
diff --git a/ui/marks.js b/ui/marks.js
index 4e8a75fc..3dee3867 100755
--- a/ui/marks.js
+++ b/ui/marks.js
@@ -221,7 +221,6 @@ var toggleMarkesView = createCSSClassToggler(
 * Actions
 */
 
-
 var toggleMark = makeMarkToggler(
 		'marked', 
 		'selected', 
@@ -230,8 +229,7 @@ var toggleMark = makeMarkToggler(
 			// add marked image to list...
 			if(action == 'on'){
 				if(MARKED.indexOf(gid) == -1){
-					MARKED.push(gid)
-					MARKED.sort(imageOrderCmp)
+					insertGIDToPosition(gid, MARKED)
 				} 
 
 			// remove marked image from list...
@@ -251,7 +249,7 @@ function toggleAllMarks(action, mode){
 	if(action == 'on'){
 		var _update = function(e){
 			if(MARKED.indexOf(e) < 0){
-				MARKED.push(e)
+				insertGIDToPosition(e, MARKED)
 				updated.push(e)
 			}
 		}
@@ -276,10 +274,6 @@ function toggleAllMarks(action, mode){
 
 	res.forEach(_update)
 
-	if(action == 'on'){
-		MARKED.sort(imageOrderCmp)
-	}
-
 	updateImages(updated)
 
 	$('.viewer').trigger('togglingMarks', [updated, action])
@@ -316,8 +310,7 @@ function invertImageMarks(){
 		var i = MARKED.indexOf(e)
 		if(i == -1){
 			on.push(e)
-			MARKED.push(e)
-			MARKED.sort(imageOrderCmp)
+			insertGIDToPosition(e, MARKED)
 		} else {
 			off.push(e)
 			MARKED.splice(i, 1)
@@ -355,7 +348,7 @@ function toggleMarkBlock(image){
 		}
 		// do the toggle...
 		if(state){
-			MARKED.push(e)
+			insertGIDToPosition(e, MARKED)
 		} else {
 			MARKED.splice(MARKED.indexOf(e), 1)
 		}
@@ -372,9 +365,6 @@ function toggleMarkBlock(image){
 	$.each(right, _convert)
 
 	updateImages(updated)
-	if(state){
-		MARKED.sort(imageOrderCmp)
-	}
 
 	$('.viewer')
 		.trigger('togglingImageBlockMarks', [image, updated, state])