Vocational teachers described maladaptive social behavior of retarded workers in vocational training classrooms and sheltered workshops. A rating scale was developed from 28 items measuring unacceptable language behavior. Twenty-seven teachers rated (a) 196 retarded workers with respect to the frequency of maladaptive behavior and (b) the 28 items with respect to the probability that a given behavior would result in termination of employment. Patterns of language behavior of retarded workers were factor analyzed, yielding two primary dimensions: verbal manners and communication skills. Irritating verbal manners were rated as more likely to result in termination of a worker than were poor communication skills. Both factors correlated significantly with the AAMD Adaptive Behavior Scale, and communication skills correlated significantly with the San Francisco Vocational Competency Scale. Results suggested the need to remediate maladaptive verbal behavior in sheltered or educational settings and to assign workers to jobs in accordance with their communication skills.