<Window x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="525">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="*" />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>
        <ItemsControl ItemsSource="{Binding Skontos}"
                      Margin="12,12,12,6">
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Grid Margin="0,6">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="Auto"></ColumnDefinition>
                            <ColumnDefinition Width="*"></ColumnDefinition>
                        </Grid.ColumnDefinitions>
                        <TextBlock Grid.Column="1"
                                   Text="{Binding Name,
                                          StringFormat='Name: {0}'}"></TextBlock>
                    </Grid>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
 
        <Button HorizontalAlignment="Right"
                VerticalAlignment="Center"
                Width="70"
                Height="23"
                Margin="12,6,12,12"
                Grid.Row="1"
                Content="Add New" Name="Button1"
                Click="Button1_Click"></Button>
    </Grid>
</Window>

Class MainWindow
    Private mSkontoCount As Integer = 0
    Public Sub New()
        InitializeComponent()
        Dim r As New Rechnung
        For i As Integer = 1 To 5
            mSkontoCount += 1
            r.Skontos.Add(New Skonto With {.Name = "Skonto " & _
              mSkontoCount.ToString()})
        Next
        Me.DataContext = r
    End Sub
 
    Private Sub Button1_Click(sender As System.Object, e As _
      System.Windows.RoutedEventArgs)
        Dim r = CType(Me.DataContext, Rechnung)
        mSkontoCount += 1
        r.Skontos.Add(New Skonto With {.Name = "Skonto " & _
          mSkontoCount.ToString()})
    End Sub
End Class
 
Public Class Rechnung
    Public Property Skontos As New System.ComponentModel.BindingList(Of Skonto)
End Class
 
Public Class Skonto
    Public Property Name As String = String.Empty
End Class