The Function-based Intervention Decision Model (Umbreit, Ferro, Liaupsin, & Lane, 2007) (Decision Model), is a straightforward technique to link the function of a behavior to an intervention. Although this technique has been found to be significantly effective with school-age disability populations, it has not been tested with adults who have cognitive disabilities and significant behavioral problems in non-school settings.This study explored the efficacy of the Decision Model (Umbreit et al., 2007) as a method for matching behavioral interventions to assessed function(s) of the target behavior by extending its practices to adults with developmental disabilities in a community-based day program. The participants were three adults with moderate mental retardation and problematic behavior, displayed by inappropriate social interactions. The research design was a multiple baseline across subjects. A notable benefit to this design is that there was no need to withdraw treatment, an important ethical consideration because each of the problem behaviors presented with some form of self-injury, aggression to others, and/or property destruction. The study had four phases: (a) conducting the functional behavioral assessment to identify the function of the participant's problem behavior, (b) utilizing the Decision Model (Umbreit et al., 2007) to link the function to the behavioral intervention plan (BIP), (c) applying the intervention, and (d) and maintenance. Several research questions were posed: (a) Do interventions developed using the Decision Model produce positive results for adults who have developmental disabilities and significant behavior problems in a non-school setting? (b) Will the application and maintenance of each BIP result in decreased exhibition of assessed problem behaviors? (c) Will the application and maintenance of each BIP result in increased exhibition of identified replacement behaviors? (d) Will the day program support staff and behavioral support team view the outcomes as socially valid? The results indicated a decrease in problem behaviors (socially inappropriate interactions) and an increase in replacement behaviors (socially appropriate interactions). Results of this study influenced positive intervention strategies that were easily maintained and viewed as socially valid by the direct support staff, evidenced by the results of the Treatment Acceptability Rating Form-Revised (Reimers, Wacker, Cooper, & DeRaad, 1992).