This study compared self-presentation and other-orientation behaviors and interaction patterns in three types of online AA groups (i.e., asynchronous discussions, formal synchronous AA meetings, and informal chats) to the behaviors and interaction patterns in other computer mediated support groups and computer mediated nonsupport (interest) groups. Results showed AA groups differed somewhat from other support groups and support groups differed from nonsupport interest groups. Asynchronous AA discussions had the highest proportion of semi-private and private-personal self-presentations, agreements, and personal acceptance. Private-personal disclosures also tended to be followed by personal acceptance. Formal synchronous AA meetings were characterized by reciprocity of private personal disclosure and informal chats between recovering alcoholics were characterized by reciprocity of personal acceptance. AA groups in particular and support groups in general engaged in fewer negative comments, and opinion disclosures were not as likely to evoke negative responses as in nonsupport interest groups. Results supported Walther's (1996) hyperpersonal model and the supportive character of online AA groups. Overall there was reciprocity of self-presentation and other-orientation, and self-presentation codes predicted the nature of other-orientation responses.