Psychotropic medications are commonly used as an adjunct treatment in large-scale residential care facilities for adults with developmental disabilities. While the benefits of medication are noted, there are very severe conditions that can result from long term medication use. Tardive dyskinesia (TD) manifests as a variety of involuntary, repetitive movements caused by a history of neuroleptic medication use. Due to the serious nature of this disorder, it is necessary to find predisposing factors for TD in a population of adults with intellectual and developmental disabilities. The current study seeks to expand the literature related to TD utilizing a measure of medication side effects, the Matson evaluation of drug side effects (MEDS). Results and implications for assessment and practice are discussed. (Contains 2 tables.)