diff --git a/src/js/select2/core.js b/src/js/select2/core.js
index cc384b0b..4ba06edb 100644
--- a/src/js/select2/core.js
+++ b/src/js/select2/core.js
@@ -185,10 +185,11 @@ define([
       self.trigger('focus', evt);
     });
 
-    this._sync = Utils.bind(this._syncAttributes, this);
+    this._syncA = Utils.bind(this._syncAttributes, this);
+    this._syncS = Utils.bind(this._syncSubtree, this);
 
     if (this.$element[0].attachEvent) {
-      this.$element[0].attachEvent('onpropertychange', this._sync);
+      this.$element[0].attachEvent('onpropertychange', this._syncA);
     }
 
     var observer = window.MutationObserver ||
@@ -198,14 +199,30 @@ define([
 
     if (observer != null) {
       this._observer = new observer(function (mutations) {
-        $.each(mutations, self._sync);
+        $.each(mutations, self._syncA);
+        $.each(mutations, self._syncS);
       });
       this._observer.observe(this.$element[0], {
         attributes: true,
+        childList: true,
         subtree: false
       });
     } else if (this.$element[0].addEventListener) {
-      this.$element[0].addEventListener('DOMAttrModified', self._sync, false);
+      this.$element[0].addEventListener(
+        'DOMAttrModified',
+        self._syncA,
+        false
+      );
+      this.$element[0].addEventListener(
+        'DOMNodeInserted',
+        self._syncS,
+        false
+      );
+      this.$element[0].addEventListener(
+        'DOMNodeRemoved',
+        self._syncS,
+        false
+      );
     }
   };
 
@@ -350,6 +367,46 @@ define([
     }
   };
 
+  Select2.prototype._syncSubtree = function (evt, mutations) {
+    var changed = false;
+    var self = this;
+
+    // Ignore any mutation events raised for elements that aren't options or
+    // optgroups. This handles the case when the select element is destroyed
+    if (
+      evt && evt.target && (
+        evt.target.nodeName !== 'OPTION' && evt.target.nodeName !== 'OPTGROUP'
+      )
+    ) {
+      return;
+    }
+
+    if (!mutations) {
+      // If mutation events aren't supported, then we can only assume that the
+      // change affected the selections
+      changed = true;
+    } else if (mutations.addedNodes && mutations.addedNodes.length > 0) {
+      for (var n = 0; n < mutations.addedNodes.length; n++) {
+        var node = mutations.addedNodes[n];
+
+        if (node.selected) {
+          changed = true;
+        }
+      }
+    } else if (mutations.removedNodes && mutations.removedNodes.length > 0) {
+      changed = true;
+    }
+
+    // Only re-pull the data if we think there is a change
+    if (changed) {
+      this.dataAdapter.current(function (currentData) {
+        self.trigger('selection:update', {
+          data: currentData
+        });
+      });
+    }
+  };
+
   /**
    * Override the trigger method to automatically trigger pre-events when
    * there are events that can be prevented.
@@ -496,7 +553,7 @@ define([
     this.$container.remove();
 
     if (this.$element[0].detachEvent) {
-      this.$element[0].detachEvent('onpropertychange', this._sync);
+      this.$element[0].detachEvent('onpropertychange', this._syncA);
     }
 
     if (this._observer != null) {
@@ -504,10 +561,15 @@ define([
       this._observer = null;
     } else if (this.$element[0].removeEventListener) {
       this.$element[0]
-        .removeEventListener('DOMAttrModified', this._sync, false);
+        .removeEventListener('DOMAttrModified', this._syncA, false);
+      this.$element[0]
+        .removeEventListener('DOMNodeInserted', this._syncS, false);
+      this.$element[0]
+        .removeEventListener('DOMNodeRemoved', this._syncS, false);
     }
 
-    this._sync = null;
+    this._syncA = null;
+    this._syncS = null;
 
     this.$element.off('.select2');
     this.$element.attr('tabindex', this.$element.data('old-tabindex'));