Okay, just to update everyone and for others that might search this mail-listing: I have finally gotten it, using the code below in the authorize section I can send host authentication to multiple proxies based on domain name if ( User-Name =~ /^host\//i ) { if ( User-Name =~ /\\.first\\.domain$/i ) { update control { Proxy-To-Realm := "first.domain" } } if ( User-Name =~ /\\.second\\.domain$/i ) { update control { Proxy-To-Realm := "second.domain" } } if ( User-Name =~ /\\.first\\.domain$/i ) { update control { Proxy-To-Realm := "third.domain" } } } For whatever reason I had to use 2 backslashes in front of the period in the domain names?? But anyway, this part of the project is working. Thanks for all the help! Bob