Used meta-analysis to examine duration of group experience and structure provided by leader in counseling groups from 26 studies. Group composition appeared to have greatest effect in unstructured group which was relatively long in duration. Leaders using short-term, structured groups may be less concerned with composition, as its potential effect…

Contrasts open and closed therapeutic groups in the context of group development research, and reanalyzes data applying the Hill Interaction Matrix. Results supported the existence of a discernable process of development in the closed groups, while open groups with residual members showed counterproductive activity. (LLL)