As a classroom demonstration in an introductory social psychology lecture at the University of Bochum in June 1970 the author replicated that part of the study by Thomas and Fink (1961) which compared the solutions of Maier's horse trading problem by groups of three members with solutions offered by individuals.The classroom consisted of two wings with an aisle in between. The left wing with 57 students was randomly assigned to the group condition, and the right wing with 54 students to the individual condition. S's in the group condition were asked to form groups of three members such that the first three students in the first row would be group 1, the next three students in that row group 2 and so forth.Procedure. S's were told that three minutes would be available for the solution of a problem and that the last 30 seconds of this solution time would be announced by E. Otherwise instructions were essentially the same as in the original study.