We evaluated the effectiveness of functional communication training (FCT) as an intervention for the problem behavior exhibited by 5 students with severe disabilities both in school and in the community. Following an assessment of the function of their problem behavior, the students were taught to use assistive communication devices in school to request the objects and activities that presumably were maintaining their behavior. Multiple baseline data collected across the students indicated that not only did the students use their devices successfully, but the intervention also reduced their problem behavior. In addition, data from community settings showed generalization to untrained community members. These results replicate other successful efforts to use FCT with individuals having limited communication skills, and demonstrate the value of teaching skills to recruit natural communities of reinforcement in order to generalize intervention effects to meaningful nontraining environments.