Two studies were conducted to assess the utilization and effectiveness of multidisciplinary teams (MDTs). The first assessed the use of MDTs in providing services to mentally handicapped (MH) and learning disabled (LD) students; the second examined factors that contributed to MDT effectiveness. Also investigated were team composition, courses into which MH and LD students were mainstreamed and selected demographic variables;A random sample of 300 school districts in three midwestern states was used. The first study had 222 responses, and the second had 218 responses;Frequencies, percentages, means and Chi-square tests of independence were used to analyze data in the first study. Data in the second study were analyzed using descriptive statistics, principal components factor analysis techniques, one-way analysis of variance and post hoc Tukey tests;Most (93.2%) of the districts were using teams to provide services to MH and LD students and were also meeting (95.0%) at least once a year. MH and LD students were mainstreamed into all subject matter areas with the most frequent placements being home economics and industrial education. A typical team of 7 members consisted of a counselor, psychologist, regular educator, school administrator, special educator and two other members depending on the child's specific needs;Four MDT effectiveness factors with acceptable reliability coefficients were identified: Components of Team Functioning, Team Decision-Making, Administrative Support and Relationships between Regular and Special Educators. Significantly higher scores on the Team Decision-Making Factor were obtained for special educators and for those who had chaired a MDT. Vocational educators placed significantly greater importance on Administrative Support in the form of inservice and preparation time.