A number of studies have established that behavior is a potent determinant of teacher expectations. Clarification of specific behaviors that influence teacher attitudes becomes increasingly important as special educators attempt to reintegrate emotionally disturbed students into regular classrooms. The current study is a survey of regular classroom teachers' attitudes toward 7 clusters of behavior based on the federal definition of emotional disturbance and typically exhibited by students in the classroom. Subjects, 139 firstthrough sixth-grade teachers, were asked to read a vignette of a hypothetical emotionally disturbed student and then respond to an attitudinal survey, an adaptation of the Learning Handicapped Integration Inventory (Watson & Hewett, 1976).Results indicated that behaviors were differentially disturbing: Teachers responded most negatively toward students characterized as aggressive and least negatively toward students characterized as avoiding their peers. A secondary finding was that regardless of the behavioral vignette they read, teachers responded with more concern for the mainstreamed student, less concern for the other students, and the least concern for themselves. The discussion relates current findings to literature on aggressive classroom behavior. Future research on the factor structure of disturbed behavior is recommended.The literature is replete with studies demonstrating that naturally occurring student characteristics often trigger probabilistic expectations or bias in teachers. While some studies have merely established the existence of bias, a number have shown that classroom interactions are affected by teacher expectancy. The major characteristics shown to have engendered negative teacher attitudes or differential teacher interactions are race (Coates