<DataGridTemplateColumn Header="Erledigt?" IsReadOnly="False"> <DataGridTemplateColumn.CellTemplate> <DataTemplate> <CheckBox Command="{Binding Path=DataContext.SetErledigtCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGrid}}}" CommandParameter="{Binding ElementName=DgSource, Path=SelectedItem}" IsChecked="{Binding DataContext.Erledigt, UpdateSourceTrigger=PropertyChanged}" /> </DataTemplate> </DataGridTemplateColumn.CellTemplate> </DataGridTemplateColumn>