I want to base my ISA 2004 Enterprise Edition install on best practice or experience from other users. Currently, our ISA 2000 array has 2 members that are member servers in a DMZ Active Directory domain. The DMZ Active Directory domain has 2 DC's. Since the array info is stored in Active Directory, and Active Directory info is replicated to both DC?s, I can count on the array being online as long as one of the 2 DC's is online. With this in mind, for the same redundancy, should I install the CSS on the DC's or both ISA array members? The option to purchase dedicated CSS is not really feasible. But if we did, should their be 2 of them? Thanks Nathan