Over a period of three years, sixty-three children were treated with a group play technique which Gibbs describes and evaluates. He differentiates this technique from free play activities in schools and play centers and from the group therapy of adults. Group play is not a substitute for individual therapy, though it is useful from an observational (diagnostic) and therapeutic point of view. In an appendix the progress notes of a single patient are extracted: a nine-year-old asthmatic, learning to express his aggression. His somatic illness receded into the background as he learned to express himself and behave in a more acceptable manner both in the group and at home At the same time the mother was seen by a social worker and gained insight into her own rôle in the production of the illness. The dynamics described are rather superficial and much more data are necessary in order to evaluate what actually happened in treatment.