Three studies examined group problem-solving on complex intellective tasks. In Study 1, a decision model proposed by Laughlin and Hollingshead (1995) provided the best fit to actual group choices. This study also compared three-person group versus individual performance with time constrained and number of problems unconstrained, with individuals solving non-significantly more problems and groups obtaining significantly superior trials-to-solution scores. In Study 2, one member of each group was given additional information on how to perform the task and member extroversion was measured. Neither factor significantly impacted the decision-making process. In Study 3, task expertise was assessed prior to the group interaction. Results indicate that group members were twice as likely to adopt an option proposed by an expert compared to other group members. Together these studies demonstrate that group problem solving is governed jointly by qualities of the task and qualities of the group members. Copyright © 2006 John Wiley & Sons, Ltd.