but i stilll dont know how to pass parameters throw showmodaldialog which am writing like main:- function show() { window.showmodaldialog("Password.aspx", "","resizable:off;dialogheight:10cm); var ss = document.getelementbyID("tbPassword").text; } child:- function showParam() { alert(window.dialogArguments); } is this valid, or some thing missing because on childpage (object expected)