Members of more than 50 student groups involved in a team problem-solving environment were surveyed with the Group Style Instrument (GSI) to examine interpersonal group processes for task groups. Analyses of the GSI data resulted in team-oriented and self-oriented dimensions for both samples by comparing several factor models. In a second sample, more than 80 culturally diverse and nondiverse groups involved in a similar team problem-solving format completed the GSI at three points in time after they had completed team projects involving substantial collaborative member effort. For Sample 2, culturally diverse teams reported more self-oriented behaviors (SOBs) over time and performed better that nondiverse teams on two of the three projects. Periodic feedback regarding team performance and interpersonal processing was given to all teams. By the third team project, nondiverse teams performed better. Emphasis is given concerning the importance of managing the balance of team-orientated behaviors and SOBs within teams over time.