Recent proliferation at training and educational programs for paraprofessional and non professionals has occurred without systematic evaluation of systems' utilization of newly trained people. It was the purpose of this study to assess both job functioning and attitudes of paraprofessionals in relation to professionals and the interaction of systems' variables that would impact the effectiveness of its individual members. A multi-method, multi-criteria study revealed significant systems, group, and individual differences between teams and team members in community mental health centers committed to medical-illness/clinical (MIC) paradigms of mental health and those committed to psycho-social learning/community (PSLC) paradigms. There were differences in teams' utilization of professionals and paraprofessionals, and psycho-social differences in the members themselves. Compared to their MIC peers, paraprofessionals in the PSLC systems experienced the system as more positive and reported themselves being utilized more fully. Also, PSLC professionals reported greater sense of cohesiveness, influence, and satisfaction with co-workers than their MIC peers. Implications of these results were discussed in terms of training for both paraprofessionals and professionals (especially with regard to transfer of learning and utilization of resources) and in terms of understanding human behavior/performance within an individual-system interaction framework. (Author)