Adults with intellectual and developmental disabilities (IDD) who also have a co-occurring mental illness are almost five times as likely to experience a delayed hospital discharge as adults with mental illness only. These delays occur when a patient no longer requires hospital-level care but cannot be discharged, often because of a lack of appropriate post-discharge settings. Delayed discharges contribute to poor patient outcomes, increased system costs, and delayed access to care. Recently, practice guidance was developed in Canada, identifying 10 components of successful transitions for this population. Core to this guidance is a patient-centered, cross-sectoral approach, including the patient, family, hospital team, community health care providers, and IDD providers.