diff --git a/Tests/ViewModels/SettingsViewModelTest.cs b/Tests/ViewModels/SettingsViewModelTest.cs
index f06d5d8..65a1d56 100755
--- a/Tests/ViewModels/SettingsViewModelTest.cs
+++ b/Tests/ViewModels/SettingsViewModelTest.cs
@@ -22,6 +22,7 @@ using System.Text;
 using NUnit.Framework;
 using zaaReloaded2.ViewModels;
 using zaaReloaded2.Controller;
+using zaaReloaded2.Controller.Elements;
 
 namespace Tests.ViewModels
 {
@@ -51,7 +52,16 @@ namespace Tests.ViewModels
         [Test]
         public void CannotAddChildElementToFormatElement()
         {
-
+            ControlElementViewModel parent = new ControlElementViewModel(
+                new SelectFirstDay());
+            _settingsVM.AddElementViewModel(parent);
+            parent.IsSelected = true;
+            Assert.IsTrue(_settingsVM.AddChildElementCommand.CanExecute(null));
+            FormatElementViewModel child = new FormatElementViewModel(new Items());
+            parent.AddChildElement(child);
+            parent.IsSelected = false;
+            child.IsSelected = true;
+            Assert.IsFalse(_settingsVM.AddChildElementCommand.CanExecute(null));
         }
 
         [Test]
diff --git a/zaaReloaded2/ViewModels/CategoryViewModel.cs b/zaaReloaded2/ViewModels/CategoryViewModel.cs
new file mode 100755
index 0000000..8402275
--- /dev/null
+++ b/zaaReloaded2/ViewModels/CategoryViewModel.cs
@@ -0,0 +1,46 @@
+/* CategoryViewModel.cs
+ * part of zaaReloaded2
+ * 
+ * Copyright 2015 Daniel Kraus
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Bovender.Mvvm.ViewModels;
+
+namespace zaaReloaded2.ViewModels
+{
+    /// <summary>
+    /// A simple view model that can be used to categorize items
+    /// in a tree view. It has a custom DisplayString and holds
+    /// a collection of child view model items.
+    /// </summary>
+    class CategoryViewModel : ViewModelBase
+    {
+        public IEnumerable<ViewModelBase> Children { get; private set; }
+
+        public CategoryViewModel(string name, IEnumerable<ViewModelBase> children)
+        {
+            DisplayString = name;
+            Children = children;
+        }
+
+        public override object RevealModelObject()
+        {
+            throw new NotImplementedException();
+        }
+    }
+}
diff --git a/zaaReloaded2/ViewModels/ControlElementViewModel.cs b/zaaReloaded2/ViewModels/ControlElementViewModel.cs
index 1826c42..c5452b1 100755
--- a/zaaReloaded2/ViewModels/ControlElementViewModel.cs
+++ b/zaaReloaded2/ViewModels/ControlElementViewModel.cs
@@ -46,5 +46,16 @@ namespace zaaReloaded2.ViewModels
         { }
 
         #endregion
+
+        #region Public methods
+
+        public void AddChildElement(FormatElementViewModel viewModel)
+        {
+            Elements.Add(viewModel);
+            ControlElementBase e = Element as ControlElementBase;
+            e.FormatElements.Add(viewModel.RevealModelObject() as FormatElementBase);
+        }
+
+        #endregion
     }
 }
diff --git a/zaaReloaded2/ViewModels/ElementPickerViewModel.cs b/zaaReloaded2/ViewModels/ElementPickerViewModel.cs
new file mode 100755
index 0000000..24d75eb
--- /dev/null
+++ b/zaaReloaded2/ViewModels/ElementPickerViewModel.cs
@@ -0,0 +1,122 @@
+/* ElementPickerViewModel.cs
+ * part of zaaReloaded2
+ * 
+ * Copyright 2015 Daniel Kraus
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Bovender.Mvvm;
+using Bovender.Mvvm.Messaging;
+using Bovender.Mvvm.ViewModels;
+using System.Collections.ObjectModel;
+using zaaReloaded2.Controller.Elements;
+
+namespace zaaReloaded2.ViewModels
+{
+    /// <summary>
+    /// View model that presents a list of zaaReloaded2.Contorller.Elements.ElementBase
+    /// classes to choose from.
+    /// </summary>
+    class ElementPickerViewModel : ViewModelBase
+    {
+        #region Properties
+
+        /// <summary>
+        /// A two-dimensional tree 
+        /// </summary>
+        public IList<CategoryViewModel> AvailableElements { get; private set; }
+
+        #endregion
+
+        #region Constructors
+
+        public ElementPickerViewModel(SettingsViewModel caller, bool allowControlElements)
+        {
+            _caller = caller;
+            AvailableElements = new List<CategoryViewModel>();
+            if (allowControlElements)
+            {
+                AvailableElements.Add(
+                    new CategoryViewModel(
+                        "Kontroll-Elemente",
+                        new Collection<ViewModelBase>()
+                        {
+                            CreateControlElementViewModel(new SelectFirstDay()),
+                            CreateControlElementViewModel(new SelectLastDay()),
+                            CreateControlElementViewModel(new SelectEachDay())
+                        }
+                    )
+                );
+            }
+            AvailableElements.Add(
+                new CategoryViewModel(
+                    "Ausgabe-Elemente",
+                    new Collection<ViewModelBase>()
+                        {
+                            CreateFormatElementViewModel("Laborparameter", new Items()),
+                            CreateFormatElementViewModel("Beliebiger Text", new CustomText()),
+                        }
+                )
+            );
+        }
+
+        #endregion
+
+        #region Private methods
+
+        /// <summary>
+        /// Creates a new ControlElementViewModel that wraps a ControlElementBase
+        /// object. The display string of the ControlElementViewModel is taken
+        /// from the canonical Label of the control element.
+        /// </summary>
+        ViewModelBase CreateControlElementViewModel(ControlElementBase element)
+        {
+            ControlElementViewModel vm = new ControlElementViewModel(element);
+            vm.DisplayString = element.Label;
+            return vm;
+        }
+
+        /// <summary>
+        /// Creates a new FormatElementViewModel that wraps a FormatElementBase
+        /// object and has a custom display string. The custom display string
+        /// is necessary because format elements do not have a canonical label.
+        /// </summary>
+        ViewModelBase CreateFormatElementViewModel(string name, FormatElementBase element)
+        {
+            FormatElementViewModel vm = new FormatElementViewModel(element);
+            vm.DisplayString = name;
+            return vm;
+        }
+
+        #endregion
+
+        #region Implementation ov ViewModelBase
+
+        public override object RevealModelObject()
+        {
+            throw new NotImplementedException();
+        }
+
+        #endregion
+
+        #region Fields
+
+        SettingsViewModel _caller;
+
+        #endregion
+    }
+}
diff --git a/zaaReloaded2/ViewModels/SettingsViewModel.cs b/zaaReloaded2/ViewModels/SettingsViewModel.cs
index b573097..c662f1b 100755
--- a/zaaReloaded2/ViewModels/SettingsViewModel.cs
+++ b/zaaReloaded2/ViewModels/SettingsViewModel.cs
@@ -22,6 +22,7 @@ using System.Linq;
 using System.Text;
 using Bovender.Mvvm;
 using Bovender.Mvvm.ViewModels;
+using Bovender.Mvvm.Messaging;
 using zaaReloaded2.Controller;
 using zaaReloaded2.Controller.Elements;
 using zaaReloaded2.Formatter;
@@ -161,6 +162,20 @@ namespace zaaReloaded2.ViewModels
             }
         }
 
+        public DelegatingCommand AddChildElementCommand
+        {
+            get
+            {
+                if (_addChildElementCommand == null)
+                {
+                    _addChildElementCommand = new DelegatingCommand(
+                        param => DoAddChildElement(),
+                        param => CanAddChildElement());
+                }
+                return _addChildElementCommand;
+            }
+        }
+
         public DelegatingCommand DeleteElementCommand
         {
             get
@@ -191,10 +206,31 @@ namespace zaaReloaded2.ViewModels
 
         #endregion
 
+        #region Public methods
+
+        /// <summary>
+        /// Wires the OnProperty changed event of an ElementViewModel's
+        /// wrapped model and adds the view model to the Elements collection.
+        /// </summary>
+        public void AddElementViewModel(ElementViewModel elementViewModel)
+        {
+            elementViewModel.PropertyChanged += ElementViewModel_PropertyChanged;
+            Elements.Add(elementViewModel);
+        }
+
+        #endregion
+
         #region Private methods
 
         void DoAddElement() { }
 
+        void DoAddChildElement() { }
+
+        bool CanAddChildElement()
+        {
+            return SelectedElement is ControlElementViewModel;
+        }
+
         void DoDeleteElement() { }
 
         bool CanDeleteElement() { return _selectedElement != null; }
@@ -203,17 +239,6 @@ namespace zaaReloaded2.ViewModels
 
         bool CanCopyElement() { return _selectedElement != null; }
 
-        /// <summary>
-        /// Internal function that creates wires the OnProperty changed event
-        /// of an ElementViewModel's wrapped model and adds the view model
-        /// to the Elements collection.
-        /// </summary>
-        void AddElementViewModel(ElementViewModel elementViewModel)
-        {
-            elementViewModel.PropertyChanged += ElementViewModel_PropertyChanged;
-            Elements.Add(elementViewModel);
-        }
-
         /// <summary>
         /// Sets or unsets the SelectedElement property whenever the IsSelected
         /// property of an ElementViewModel changes.
@@ -251,8 +276,10 @@ namespace zaaReloaded2.ViewModels
 
         Settings _settings;
         DelegatingCommand _addElementCommand;
+        DelegatingCommand _addChildElementCommand;
         DelegatingCommand _deleteElementCommand;
         DelegatingCommand _copyElementCommand;
+        
         List<ElementViewModel> _elements;
         ElementViewModel _selectedElement;
         EnumProvider<ReferenceStyle> _referenceStyle;
diff --git a/zaaReloaded2/zaaReloaded2.csproj b/zaaReloaded2/zaaReloaded2.csproj
index 07a446a..d595215 100755
--- a/zaaReloaded2/zaaReloaded2.csproj
+++ b/zaaReloaded2/zaaReloaded2.csproj
@@ -219,6 +219,8 @@
     </Compile>
     <Compile Include="Updater\Updater.cs" />
     <Compile Include="ViewModels\AboutViewModel.cs" />
+    <Compile Include="ViewModels\CategoryViewModel.cs" />
+    <Compile Include="ViewModels\ElementPickerViewModel.cs" />
     <Compile Include="ViewModels\ElementViewModel.cs" />
     <Compile Include="ViewModels\FormatElementViewModel.cs" />
     <Compile Include="ViewModels\ControlElementViewModel.cs" />