Two means of exploring what happened in one group marathon ( N = 15) were used. Several statements can be made about the results: (1) Change occurred during the 24 hr. of the marathon in group structure as well as relationships within that structure. (2) Change was most evident in the “mean” population of the group—those persons seen as above or below chance at the onset—not the “extremes”—the leader or the unchosen. (3) Acceptance in a group, as measured by a target sociogram, was not achieved by psychological helpfulness, as measured by the post-marathon evaluation questionnaire. (4) Aggression-confrontation was not perceived as being as important a parameter as empathic identification or acceptance-warmth. (5) The statement: “I was least helpful…” elicited a high response from the participants on the aggression-confrontation dimension as well as the “write-in” dimension. (6) Profiles of helpfulness given, helpfulness received, least helpfulness given, and least helpfulness received differ markedly on the five dimensions of psychological helpfulness perceived by the group sampled in this study.