The research literature provides no definitive data regarding the relative prevalence of trauma exposure and PTSD in individuals with developmental disabilities compared to individuals without developmental disabilities. Epidemiological research needs to examine this issue in detail to establish the degree of the problem in this group, using validated measures, clear definitions of terms, and random sampling procedures. In addition, individuals with developmental disabilities may require special programs targeted for their needs, but these programs need to be created without misrepresenting the current scientific status of this area. Clinical evaluations should systematically assess individuals with developmental disabilities for trauma exposure and PTSD. Finally, research is needed that uses solid assessment tools, multimodal assessment, comparison groups, and clearly defined samples. Funding to support these efforts is necessary and should involve community-researcher collaborations. Chart, notes, author biographies, 5 suggested future readings, and 86 references