Children and adults with developmental disabilities are more likely to evince encopresis, soiling and constipation than the general population. This set of related behaviors can produce a great deal of stress and can be a major restriction in independent living. This paper provides a review of the current state of knowledge on the prevalence, etiology, assessment and treatment of this co-occurring set of disorders. These problems are more common in persons with developmental disabilities then the general population. Furthermore, classical and operant treatment methods appear to be the best supported interventions for most cases. Strengths and weaknesses of the current research base are discussed along with potential avenues for future research.