Amazon.com description: Product Description: Anyone aware of the burgeoning accumulation of literature on encounter groups may well ask, "Is this book necessary?" Our answer has been affirmative because the explosive expansion of the use of groups for personal change has not been matched by corresponding concern about what such groups do and how well they do it. Innovation has exceeded evaluation. Our efforts have centered on discovering what actually happens to people in encounter groups: Who benefits, who is harmed, and what aspects of the group experience, the behavior of the leader, and the person himself, explain these effects?