Access to public community job-training sites can be restricted if students with moderate mental retardation exhibit behavior unacceptable to nondisabled coworkers or the general public. The authors conducted a functional behavioral assessment (FBA) in public community settings to determine the function of each student's problem behavior. They used a multiple-baseline-across-time sample design with behavioral probes embedded within a withdrawal to determine a functional relationship between the independent and dependent variables. The use of self-operated auditory prompts matched to maintaining functions was the function-based intervention. Problem behavior was reduced to criterion for all four students during job training in public community settings. (Contains 2 tables and 8 figures.)