diff --git a/src/timeline/Timeline.js b/src/timeline/Timeline.js
index 4fc29cab..16ae1181 100644
--- a/src/timeline/Timeline.js
+++ b/src/timeline/Timeline.js
@@ -245,7 +245,7 @@ function Timeline (container, items, options) {
     width: null,
     height: null
   });
-  this.itemSet = new ItemSet(this.backgroundPanel, this.axisPanel, itemOptions);
+  this.itemSet = new ItemSet(this.backgroundPanel, this.axisPanel, this.sideContentPanel, itemOptions);
   this.itemSet.setRange(this.range);
   this.itemSet.on('change', me.rootPanel.repaint.bind(me.rootPanel));
   this.contentPanel.appendChild(this.itemSet);
diff --git a/src/timeline/component/Group.js b/src/timeline/component/Group.js
index b7fc6d2d..e2d75c87 100644
--- a/src/timeline/component/Group.js
+++ b/src/timeline/component/Group.js
@@ -1,11 +1,14 @@
 /**
  * @constructor Group
  * @param {Number | String} groupId
+ * @param {ItemSet} itemSet
  */
-function Group (groupId) {
+function Group (groupId, itemSet) {
   this.groupId = groupId;
-  this.dom = {};
 
+  this.itemSet = itemSet;
+
+  this.dom = {};
   this.items = {}; // items filtered by groupId of this group
 
   this._create();
@@ -25,15 +28,68 @@ Group.prototype._create = function() {
   label.appendChild(inner);
   this.dom.inner = inner;
 
-  this.dom.group = document.createElement('div');
+  var group = document.createElement('div');
+  group.className = 'group';
+  group['timeline-group'] = this;
+  this.dom.group = group;
+};
+
+/**
+ * Get the foreground container element
+ * @return {HTMLElement} foreground
+ */
+Group.prototype.getForeground = function getForeground() {
+  return this.dom.group;
 };
 
 /**
- * Repaint the group
- * @return {boolean} Returns true if the component is resized
+ * Get the background container element
+ * @return {HTMLElement} background
  */
-Group.prototype.repaint = function repaint() {
-  // TODO: implement Group.repaint
+Group.prototype.getBackground = function getBackground() {
+  return this.itemSet.getBackground();
+};
+
+/**
+ * Get the axis container element
+ * @return {HTMLElement} axis
+ */
+Group.prototype.getAxis = function getAxis() {
+  return this.itemSet.getAxis();
+};
+
+/**
+ * Get the height of the itemsets background
+ * @return {Number} height
+ */
+Group.prototype.getBackgroundHeight = function getBackgroundHeight() {
+  return this.itemSet.height;
+};
+
+/**
+ * Show this group: attach to the DOM
+ */
+Group.prototype.show = function show() {
+  if (!this.dom.label.parentNode) {
+    this.itemSet.getLabelSet().appendChild(this.dom.label);
+  }
+
+  if (!this.dom.group.parentNode) {
+    this.itemSet.getForeground().appendChild(this.dom.group);
+  }
+};
+
+/**
+ * Hide this group: remove from the DOM
+ */
+Group.prototype.hide = function hide() {
+  if (this.dom.label.parentNode) {
+    this.dom.label.parentNode.removeChild(this.dom.label);
+  }
+
+  if (this.dom.group.parentNode) {
+    this.dom.group.parentNode.removeChild(this.dom.group);
+  }
 };
 
 /**
@@ -42,6 +98,7 @@ Group.prototype.repaint = function repaint() {
  */
 Group.prototype.add = function add(item) {
   this.items[item.id] = item;
+  item.setParent(this);
 };
 
 /**
@@ -50,5 +107,6 @@ Group.prototype.add = function add(item) {
  */
 Group.prototype.remove = function remove(item) {
   delete this.items[item.id];
+  item.setParent(this.itemSet);
 };
 
diff --git a/src/timeline/component/ItemSet.js b/src/timeline/component/ItemSet.js
index d07073c1..842bb0ed 100644
--- a/src/timeline/component/ItemSet.js
+++ b/src/timeline/component/ItemSet.js
@@ -6,17 +6,19 @@
  *                                vertical lines of box items.
  * @param {Panel} axisPanel       Panel on the axis where the dots of box-items
  *                                can be displayed.
+ * @param {Panel} labelPanel      Left side panel holding labels
  * @param {Object} [options]      See ItemSet.setOptions for the available options.
  * @constructor ItemSet
  * @extends Panel
  */
-function ItemSet(backgroundPanel, axisPanel, options) {
+function ItemSet(backgroundPanel, axisPanel, labelPanel, options) {
   this.id = util.randomUUID();
 
   // one options object is shared by this itemset and all its items
   this.options = options || {};
   this.backgroundPanel = backgroundPanel;
   this.axisPanel = axisPanel;
+  this.labelPanel = labelPanel;
   this.itemOptions = Object.create(this.options);
   this.dom = {};
   this.props = {
@@ -377,7 +379,9 @@ ItemSet.prototype.repaint = function repaint() {
       asString = util.option.asString,
       options = this.options,
       orientation = this.getOption('orientation'),
-      frame = this.frame;
+      frame = this.frame,
+      initialPosByStart,
+      i, ii;
 
   // update className
   frame.className = 'itemset' + (options.className ? (' ' + asString(options.className)) : '');
@@ -395,35 +399,39 @@ ItemSet.prototype.repaint = function repaint() {
   // first check if the items that were in view previously are still in view.
   // this handles the case for the ItemRange that is both before and after the current one.
   if (this.visibleItems.length > 0) {
-    for (var i = 0; i < this.visibleItems.length; i++) {
+    for (i = 0; i < this.visibleItems.length; i++) {
       this._checkIfVisible(this.visibleItems[i], newVisibleItems);
     }
   }
   this.visibleItems = newVisibleItems;
 
   // If there were no visible items previously, use binarySearch to find a visible ItemPoint or ItemRange (based on startTime)
-  if (this.visibleItems.length == 0) {var initialPosByStart = this._binarySearch(false);}
-  else                               {var initialPosByStart = orderedItems.byStart.indexOf(this.visibleItems[0]);}
+  if (this.visibleItems.length == 0) {
+    initialPosByStart = this._binarySearch(false);
+  }
+  else {
+    initialPosByStart = orderedItems.byStart.indexOf(this.visibleItems[0]);
+  }
 
   // use visible search to find a visible ItemRange (only based on endTime)
   var initialPosByEnd = this._binarySearch(true);
 
   // if we found a initial ID to use, trace it up and down until we meet an invisible item.
   if (initialPosByStart != -1) {
-    for (var i = initialPosByStart; i >= 0; i--) {
+    for (i = initialPosByStart; i >= 0; i--) {
       if (this._checkIfInvisible(orderedItems.byStart[i])) {break;}
     }
-    for (var i = initialPosByStart + 1; i < orderedItems.byStart.length; i++) {
+    for (i = initialPosByStart + 1; i < orderedItems.byStart.length; i++) {
       if (this._checkIfInvisible(orderedItems.byStart[i])) {break;}
     }
   }
 
   // if we found a initial ID to use, trace it up and down until we meet an invisible item.
   if (initialPosByEnd != -1) {
-    for (var i = initialPosByEnd; i >= 0; i--) {
+    for (i = initialPosByEnd; i >= 0; i--) {
       if (this._checkIfInvisible(orderedItems.byEnd[i])) {break;}
     }
-    for (var i = initialPosByEnd + 1; i < orderedItems.byEnd.length; i++) {
+    for (i = initialPosByEnd + 1; i < orderedItems.byEnd.length; i++) {
       if (this._checkIfInvisible(orderedItems.byEnd[i])) {break;}
     }
   }
@@ -433,7 +441,7 @@ ItemSet.prototype.repaint = function repaint() {
   var force = this.stackDirty || zoomed; // force re-stacking of all items if true
   this.stack.stack(this.visibleItems, force);
   this.stackDirty = false;
-  for (var i = 0, ii = this.visibleItems.length; i < ii; i++) {
+  for (i = 0, ii = this.visibleItems.length; i < ii; i++) {
     this.visibleItems[i].repositionY();
   }
 
@@ -507,6 +515,14 @@ ItemSet.prototype.getAxis = function getAxis() {
   return this.dom.axis;
 };
 
+/**
+ * Get the element for the labelset
+ * @return {HTMLElement} labelSet
+ */
+ItemSet.prototype.getLabelSet = function getLabelSet() {
+  return this.labelPanel.frame;
+};
+
 /**
  * Set items
  * @param {vis.DataSet | null} items
@@ -596,7 +612,7 @@ ItemSet.prototype.setGroups = function setGroups(groups) {
       me.groupsData.on(event, callback, id);
     });
 
-    // draw all new groups
+    // draw all ms
     ids = this.groupsData.getIds();
     this._onAddGroups(ids);
   }
@@ -742,7 +758,7 @@ ItemSet.prototype._onAddGroups = function _onAddGroups(ids) {
         height: null
       });
 
-      group = new Group(id);
+      group = new Group(id, me, me.dom.background, me.dom.axis, me.labelPanel.frame);
       me.groups[id] = group;
 
       // add items with this groupId to the new group
@@ -754,6 +770,8 @@ ItemSet.prototype._onAddGroups = function _onAddGroups(ids) {
           }
         }
       }
+
+      group.show();
     }
   });
 
@@ -771,10 +789,7 @@ ItemSet.prototype._onRemoveGroups = function _onRemoveGroups(ids) {
     var group = groups[id];
 
     if (group) {
-      /* TODO
-      group.setItems(); // detach items data
-      group.hide(); // FIXME: for some reason when doing setItems after hide, setItems again makes the label visible
-      */
+      group.hide();
       delete groups[id];
     }
   });
@@ -906,6 +921,14 @@ ItemSet.prototype.getLabelsWidth = function getLabelsWidth() {
   return this.props.labels.width;
 };
 
+/**
+ * Get the height of the itemsets background
+ * @return {Number} height
+ */
+ItemSet.prototype.getBackgroundHeight = function getBackgroundHeight() {
+  return this.height;
+};
+
 /**
  * Start dragging the selected events
  * @param {Event} event
@@ -1073,7 +1096,13 @@ ItemSet.itemFromTarget = function itemFromTarget (event) {
  * @return {Group | null} group
  */
 ItemSet.groupFromTarget = function groupFromTarget (event) {
-  // TODO: implement groupFromTarget
+  var target = event.target;
+  while (target) {
+    if (target.hasOwnProperty('timeline-group')) {
+      return target['timeline-group'];
+    }
+    target = target.parentNode;
+  }
 
   return null;
 };
diff --git a/src/timeline/component/item/Item.js b/src/timeline/component/item/Item.js
index b0d4b074..f8a46828 100644
--- a/src/timeline/component/item/Item.js
+++ b/src/timeline/component/item/Item.js
@@ -1,6 +1,6 @@
 /**
  * @constructor Item
- * @param {ItemSet} parent
+ * @param {ItemSet | Group} parent
  * @param {Object} data             Object containing (optional) parameters type,
  *                                  start, end, content, group, className.
  * @param {Object} [options]        Options to set initial property values
@@ -41,6 +41,23 @@ Item.prototype.unselect = function unselect() {
   if (this.displayed) this.repaint();
 };
 
+/**
+ * Set a parent for the item
+ * @param {ItemSet | Group} parent
+ */
+Item.prototype.setParent = function setParent(parent) {
+  if (this.displayed) {
+    this.hide();
+    this.parent = parent;
+    if (this.parent) {
+      this.show();
+    }
+  }
+  else {
+    this.parent = parent;
+  }
+};
+
 /**
  * Show the Item in the DOM (when not already visible)
  * @return {Boolean} changed
diff --git a/src/timeline/component/item/ItemBox.js b/src/timeline/component/item/ItemBox.js
index 05aa8ffb..df8d6fed 100644
--- a/src/timeline/component/item/ItemBox.js
+++ b/src/timeline/component/item/ItemBox.js
@@ -216,13 +216,13 @@ ItemBox.prototype.repositionY = function repositionY () {
 
     line.style.top = '0';
     line.style.bottom = '';
-    line.style.height = (this.parent.top + this.top + 1) + 'px';
+    line.style.height = (this.top + 1) + 'px';
   }
   else { // orientation 'bottom'
     box.style.top = '';
     box.style.bottom = (this.top || 0) + 'px';
 
-    line.style.top = (this.parent.top + this.parent.height - this.top - 1) + 'px';
+    line.style.top = (this.parent.getBackgroundHeight() - this.top - 1) + 'px';
     line.style.bottom = '0';
     line.style.height = '';
   }