Hi Steven, thanks for your reply.  Perhaps my question was too general.
Allow me to be a bit more specific.

   I have a simple web user control with a button and a div on it.  On the
containing page, I have a ScriptManager with EnablePageMethods=true.
When the user clicks the button, I would like it to log the time into the
'timelog' div.  What actually happens though, is that when I click the
button, I get a javascript error claiming that PageMethods is not defined.
My question is whether using a webmethod within a user control is supported,
and if not, if there is another way to do this?

Here's the .ascx:

<%@ Control Language="C#" AutoEventWireup="true"
CodeBehind="MyUserControl.ascx.cs" Inherits="MyUserControl" %>
<%@ Register Assembly="System.Web.Extensions, Version=1.0.61025.0,
Culture=neutral, PublicKeyToken=31bf3856ad364e35"
Namespace="System.Web.UI" TagPrefix="asp" %>

<script type="text/javascript">
   function RetrieveTime(controlId){
       PageMethods.GetTime(controlId,ReceiveTime);
   }
   function ReceiveTime(time){
       document.getElementById('timeLog').innerHTML += '<br />' + time;
   }
</script>

<asp:ScriptManagerProxy ID="ScriptManagerProxy1"
runat="server"></asp:ScriptManagerProxy>
<input id="Button1" type="button" value="button"
onclick="RetrieveTime(this.id);"/>
<div id="timeLog"></div>

========== And here's the code-behind ============

public partial class MyUserControl : System.Web.UI.UserControl
{
   protected void Page_Load(object sender, EventArgs e)
   {
   }

   [WebMethod]
   public static String GetTime(String controlId)
   {
       return System.DateTime.Now.ToString();
   }
}