 <p>This is what the <a href="http://msdn.microsoft.com/en-us/library/vstudio/ms227424.aspx" rel="nofollow"><code>ValidationGroup</code></a> property is for. Suppose you have the following controls:</p> <pre><code>&lt;asp:RequiredFieldValidator ID="rfv1" runat="server" ValidationGroup="Group1" /&gt; &lt;asp:RequiredFieldValidator ID="rfv2" runat="server" ValidationGroup="Group1" /&gt; &lt;asp:RequiredFieldValidator ID="rfv3" runat="server" ValidationGroup="Group2" /&gt; &lt;asp:Button ID="btn1" runat="server" ValidationGroup="Group1" Text="Button 1" /&gt; &lt;asp:Button ID="btn2" runat="server" ValidationGroup="Group2" Text="Button 2" /&gt; </code></pre> <p>In the example above, <code>btn1</code> will only cause validation for the controls validated by <code>rfv1</code> and <code>rfv2</code>, whilst <code>btn2</code> will only cause validation for the control validated by <code>rfv3</code>.</p>