WPF DataGrid ItemsSource Issue

Please let it be known that I am relatively new to WPF. I am creating a new `ObservableCollection` with the type of my simple data class, and assigning that to the `ItemsSource` property of my `DataGrid`. Before I go into my problem here is the code: XAML: ``` <my:DataGrid SelectionMode="Single" SelectionUnit="Cell" Height="113" HorizontalAlignment="Left" Margin="11,22,0,0" Name="addressGrid" VerticalAlignment="Top" Width="213" Background="#FFE2E2E2" AlternatingRowBackground="#FFA4CFF2" BorderBrush="#FF7C7C7C" HorizontalGridLinesBrush="White" PreviewKeyDown="addressGrid_PreviewKeyDown" CellEditEnding="addressGrid_CellEditEnding" BeginningEdit="addressGrid_BeginningEdit" PreparingCellForEdit="addressGrid_PreparingCellForEdit"> <my:DataGrid.Columns> <my:DataGridTextColumn Header="Name" Width="*" Binding="{Binding Path=Name}"></my:DataGridTextColumn> <my:DataGridTextColumn Header="Value" Width="3*" Binding="{Binding Path=Value}"></my:DataGridTextColumn> <my:DataGridTextColumn Header="Index" Visibility="Hidden" Binding="{Binding Path=Index}"></my:DataGridTextColumn> </my:DataGrid.Columns> </my:DataGrid> ``` Data Class: ``` public class PropertyFields { public string Name { get; set; } public object Value { get; set; } public int Index { get; set; } } ``` Population: ``` ObservableCollection<PropertyFields> propertyList = new ObservableCollection<PropertyFields>(); for (int i = 0; i < m_pFields.FieldCount - 1; ++i) { propertyList.Add(new PropertyFields() {Name = m_pFields.Field[i].AliasName, Value = DisplayedValueForRow(i), Index = i}); } // Set ItemSource to populate grid addressGrid.ItemsSource = propertyList; ``` More information about the population method: I am building this solution with ArcGIS framework, so some things are not "System" in ways. `m_pFields` is an `IFields` interface object that allows me to store spatial layer information `IFields` has a `FieldCount` property which returns a number of fields in the collection `DisplayedValueForRow(i)` calls another ArcGIS obj method `IPropertySet.GetProperty()` and returns the value. The Problem: Everything is being populated as it should be, but for some odd reason it is re-creating the three columns (Name, Value, Index) again ON TOP of populating the ones created in XAML -- In turn ending up with 2 sets of the same data. I found this to be weird behavior, as I swear I have seen people bind to their grid this way before. What am I doing wrong? Edit Thanks to ChrisO's comment, I found out that there is a property called "AutoGenerateColumns" that needed to be turned off. Well I feel like a heel. Thanks!