Best group member, When a user does a specific action on domain1.com I want a cookie to be set so that domain1.com and domain2.com can reach it. Ok, after reading the manual for setcookie() I tried this: setcookie("thevariable", "thevalue", time()+60*60*24*30, "/", ".domain1.com"); setcookie("thevariable", "thevalue", time()+60*60*24*30, "/", ".domain2.com"); However, I can not detect the cookie at domain2.com. A solution would be to just make a redirect to the other domain where the cookie is set and then return. Question is: Can I not set a cookie at domain1.com to work at domain2.com? Best regards, Peter Lauri