Programmatically remove item (of type Grid) from ListBox

Hi, I have a listbox 0 or more rows. Each row consists of 4 columns (using the Grid control to perform layout). One of those columns is a delete button. I have the handler hooked up for the delete button, but I don't know how to actually remove the (grid) item from the listbox. Here is my XAML code:
 <ListBox x:Name="FilesList" Grid.Column="0" Grid.Row="0" ItemsSource="{Binding Mode=OneWay}">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <Grid>
                  &nbs ...