diff --git a/public/js/demo/vc.html b/public/js/demo/vc.html
index d4924e4..853d07e 100644
--- a/public/js/demo/vc.html
+++ b/public/js/demo/vc.html
@@ -60,6 +60,14 @@
     };
     var vc = KorAP.VirtualCollection.render(json);
     document.getElementById('vc').appendChild(vc.element());
+
+    function showJSON() {
+      document.getElementById("json").innerHTML = JSON.stringify(vc.root().toJson());
+    };
+
     </script>
+
+    <p><a onclick="showJSON()" style="cursor:pointer">show JSON!</a></p>
+    <div id="json" style="background-color:white; color: black; padding: 1em; font-family: mono;"></div>
   </body>
 </html>
diff --git a/public/js/spec/vcSpec.js b/public/js/spec/vcSpec.js
index 2010adf..aa57b4f 100644
--- a/public/js/spec/vcSpec.js
+++ b/public/js/spec/vcSpec.js
@@ -628,9 +628,55 @@
     expect(second.matchop()).toEqual('eq');
   });
 
+
   it('should be based on a nested docGroup', function () {
     var vc = KorAP.VirtualCollection.render({
       "@type" : "korap:docGroup",
+      "operation" : "operation:or",
+      "operands" : [
+	{
+	  "@type": 'korap:doc',
+	  "key" : 'author',
+	  "match": 'match:eq',
+	  "value": 'Max Birkendale',
+	  "type": 'type:string'
+	},
+	{
+	  "@type" : "korap:docGroup",
+	  "operation" : "operation:and",
+	  "operands" : [
+	    {
+	      "@type": 'korap:doc',
+	      "key": 'pubDate',
+	      "match": 'match:geq',
+	      "value": '2014-05-12',
+	      "type": 'type:date'
+	    },
+	    {
+	      "@type": 'korap:doc',
+	      "key": 'pubDate',
+	      "match": 'match:leq',
+	      "value": '2014-12-05',
+	      "type": 'type:date'
+	    }
+	  ]
+	}
+      ]
+    });
+    expect(vc.element().getAttribute('class')).toEqual('vc');
+    expect(vc.element().firstChild.getAttribute('class')).toEqual('docGroup');
+    expect(vc.element().firstChild.children[0].getAttribute('class')).toEqual('doc');
+    var dg = vc.element().firstChild.children[1];
+    expect(dg.getAttribute('class')).toEqual('docGroup');
+    expect(dg.children[0].getAttribute('class')).toEqual('doc');
+    expect(dg.children[1].getAttribute('class')).toEqual('doc');
+    expect(dg.children[2].getAttribute('class')).toEqual('operators');
+    expect(vc.element().firstChild.children[2].getAttribute('class')).toEqual('operators');
+  });    
+
+  it('should be modifiable by deletion', function () {
+    var vc = KorAP.VirtualCollection.render({
+      "@type" : "korap:docGroup",
       "operation" : "operation:and",
       "operands" : [
 	{
@@ -660,39 +706,21 @@
     var docGroup = vc.root();
     var doc = docGroup.getOperand(1);
     expect(doc.key()).toEqual("pubDate");
-    expect(docGroup.delOperand(doc)).toEqual(true);
+
+    // Remove operand 1
+    expect(docGroup.delOperand(doc)).not.toBeUndefined();
+    expect(doc._element).toEqual(undefined);
+
     doc = docGroup.getOperand(1);
     expect(doc.key()).toEqual("foo");
-  });    
 
-  it('should be modifiable', function () {
-    var vc = KorAP.VirtualCollection.render();
+    // Remove operand 1
+    expect(docGroup.delOperand(doc)).not.toBeUndefined();
+    expect(doc._element).toEqual(undefined);
 
-    var vc = KorAP.VirtualCollection.render({
-      "@type" : "korap:docGroup",
-      "operation" : "operation:and",
-      "operands" : [
-	{
-	  "@type": 'korap:doc',
-	  "key" : 'author',
-	  "match": 'match:eq',
-	  "value": 'Max Birkendale',
-	  "type": 'type:string'
-	},
-	{
-	  "@type": 'korap:doc',
-	  "key": 'pubDate',
-	  "match": 'match:eq',
-	  "value": '2014-12-05',
-	  "type": 'type:date'
-	}
-      ]
-    });
-
-    expect(vc.element().getAttribute('class')).toEqual('vc');
-    expect(vc.root().element().getAttribute('class')).toEqual('docGroup');
-    expect(vc.root().operation()).toEqual('and');
-  });
+    // Only one operand - but there shouldn't be a group anymore!
+    expect(docGroup.getOperand(1)).toBeUndefined();
+  }); 
 });
 
 describe('KorAP.Operators', function () {
diff --git a/public/js/src/vc.js b/public/js/src/vc.js
index fbdc118..31ddc85 100644
--- a/public/js/src/vc.js
+++ b/public/js/src/vc.js
@@ -170,6 +170,7 @@
 	this._parent = obj;
       return this._parent;
     },
+
     element : function () {
 
       // Return existing element
@@ -262,6 +263,7 @@
 	obj._parent = parent;
       return obj;
     },
+
     update : function () {
       if (this._element === undefined)
 	return this.element();
@@ -531,17 +533,26 @@
       };
     },
     update : function () {
+      if (this._operands.length == 1) {
+	if (this.parent() !== undefined) {
+	  return this.parent().replaceOperand(
+	    this,
+	    this.getOperand(0)
+	  );
+	};
+      };
+
       if (this._element === undefined)
-	return this.element();
+	return this;
 
-      var op = this._element;
-      op.setAttribute('data-operation', this.operation());
+      var group = this._element;
+      group.setAttribute('data-operation', this.operation());
 
-      _removeChildren(op);
+      _removeChildren(group);
 
       // Append operands
-      for (var i in this.operands()) {
-	op.appendChild(
+      for (var i in this._operands) {
+	group.appendChild(
 	  this.getOperand(i).element()
 	);
       };
@@ -553,11 +564,11 @@
 	true
       );
 
-      this._element.appendChild(
+      group.appendChild(
 	op.element()
       );
 
-      return op;
+      return this;
     },
     element : function () {
       if (this._element !== undefined)
@@ -589,19 +600,35 @@
       return this._operands[index];
     },
 
+    // Replace operand
+    replaceOperand : function (group, obj) {
+      for (var i in this._operands) {
+	if (this._operands[i] === group) {
+	  this._operands[i] = obj;
+	  group.destroy();
+	  return this.update();
+	}
+      };
+      return false;
+    },
+
     // Delete operand from group
     delOperand : function (obj) {
       for (var i in this._operands) {
 	if (this._operands[i] === obj) {
 	  this._operands.splice(i,1);
 
+	  // Destroy object for cyclic references
+	  obj.destroy();
+
 	  // Todo: Update has to check
 	  // that this may mean the group is empty etc.
-	  this.update();
-	  return true;
+	  return this.update();
 	};
       };
-      return false;
+
+      // Operand not found
+      return undefined;
     },
 
     // Deserialize from json
@@ -679,6 +706,26 @@
       return this._parent;
     },
 
+    // Destroy object - especially for
+    // acyclic structures!
+    // I'm a paranoid chicken!
+    destroy : function () {
+      if (this._ops != undefined) {
+	this._ops._parent = undefined;
+	if (this._ops._element !== undefined)
+	  this._ops._element.refTo = undefined;
+	this._ops = undefined;
+      };
+      if (this._element !== undefined)
+	this._element = undefined;
+
+      // In case of a group, destroy all operands
+      if (this._operands !== undefined) {
+	for (var i in this._operands)
+	  this.getOperand(i).destroy();
+      };
+    },
+
     // Be aware! This may be cyclic
     operators : function (and, or, del) {
       if (arguments === 0)