An e-mail firewall (105) applies policies to e-mail messages (204) between a first site and a plurality of second sites in accordance with a plurality of administrator selectable policies (216). The firewall comprises a simple mail transfer protocol (SMTP) relay (202) for causing the e-mail messages (204) to be transmitted between the first site and selected ones of the second sites. A plurality of policy managers (216) enforce-administrator selectable policies. The policies comprise at least a first source/destination policy (218), a first content policy (202) and a first virus policy (224). The policies are characterized by a plurality of administrator selectable criteria (310), and a plurality of administrator selectable exceptions (312) to the criteria.