GroupCodeDisplay.cs

<ListBox ItemsSource="{Binding FilteredOperationCodes, Mode=OneWay}" SelectedItem="{Binding SelectedOperationCode}" SelectionMode="Single">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <Grid Margin="3">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="Auto" MinWidth="200" />
                    <ColumnDefinition Width="*"/>
                </Grid.ColumnDefinitions>
                <Grid.RowDefinitions>
                    <RowDefinition Height="Auto"/>
                    <RowDefinition Height="Auto"/>
                </Grid.RowDefinitions>
                <TextBlock Grid.Row="0" Grid.RowSpan="2" Style="{StaticResource Title}" Text="{Binding OpCd}"/>

                <TextBlock Grid.Row="0" Grid.Column="1" Style="{StaticResource Emphasis}" Text="{Binding Description}"/>
                
                <!-- This is what I'd like to change to use GroupCodeDescription -->
                <TextBlock Grid.Row="1" Grid.Column="1" Style="{StaticResource Small}" Text="{Binding GroupCode}"/>
            </Grid>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>