Hi , I am working on MOSS 2007. there are two different lists in my site. 1st list contain some information about vendor and second list contain all the detail information about vendor. I have created one user control in asp.net. there are two gridview in user control. main list bind to 1st gridview. in first gridview ID filed is linkbutton field. My requirement is, when user click on ID linkbutton then detail list should bind to second gridview. that second gridview should display exactly below of that row. I have successfuly bind both the gridview but i dont know hot to display both gridview in treeview manner. this is my first gridview. when user click on linkbutton then OnRowCommand evet is fire n second second list bind to second gridview. < asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" CellPadding ="4" Width="100%" BackColor="White" BorderColor="#336666" BorderStyle ="Double" BorderWidth="3px" GridLines="Horizontal" EnableModelValidation="True" OnRowCommand="GridView1_RowCommand"> <Columns > <asp:TemplateField HeaderText ="Report No"> <ItemTemplate > <asp:LinkButton ID="lblReportNo" runat="server" Text='<%# Eval("ID") %>' PostBackUrl="~/Default.aspx" CommandName ="View"> </asp:LinkButton > <asp:HiddenField ID="HiddenField1" runat="server" /> </ItemTemplate > <HeaderStyle ForeColor="Black" /> </asp:TemplateField> </Column> This is my second gridview. < asp:GridView ID="gvMain" runat="server" AutoGenerateColumns="False" BackColor="LemonChiffon" BorderColor="#336666" BorderStyle="Double" BorderWidth="2px" CellPadding="2" Font-Bold="True" GridLines="Horizontal" Height="55px" Width ="644px"> <Columns > <asp:TemplateField HeaderText ="Description"> <ItemTemplate > <asp:Label ID="lbldscption" runat="server" Text='<%# Eval("Description") %>'></asp:Label > </ItemTemplate > <HeaderStyle ForeColor="White" /> </asp:TemplateField > Can anybody tell me how to use nested gridview.?