The following is a snippet of my own code and it works. Give it a shot by replacing in your own variables.

Response.Write "NIRHB Patient List for " & request("docname")

Your own code was:

you requested record number < %= Request.QueryString("cust_id") % >

with a url of:

localhost/mytest/test.asp?cust_id=1


Your code should be working properly the way you have it but try it like this just to see (without the spaces at the start and end of course):

< %
Response.Write "You requested record number " & Request("cust_id")
% >