Self-help groups have become important resources for families of persons with mental illness. The present study was an attempt to understand the factors perceived by group members as helpful using Yalom's factors in clarifying the dynamics of groups. Members (N = 202) of the Alliance for the Mentally Ill of Pennsylvania (AMI of PA), an association of self-help groups for families of the mentally ill, were recruited and responded to a self-administered questionnaire. Hierarchical block multiple regression indicated that those AMI members who felt information provision and gaining support and self-understanding from the group process was helpful and were longer term participants in their group were more likely to perceive benefit from belonging to the group. The findings may provide the basis for evaluating and improving self-help group effectiveness and contribute to understanding process factors within a self-help group which members find beneficial. Implications for how these groups can attract and maintain members are discussed.