Developmental disabilities are attributable to a cognitive impairment, physical impairment, or both. They manifest during the developmental period from birth to early adulthood, and are likely to continue indefinitely. The life expectancy of most persons with developmental disabilities now approaches that of the general population. According to the neurodiversity model of care, developmental disability is accepted as a valued part of human neurologic diversity. The social model focuses on improving participation in society with accommodations such as adaptive equipment or improvements to the social and physical environment. The goal of health care for patients with developmental disabilities is to improve their well-being, function, and participation in family and community. Physicians should communicate directly with their patients, even those who have communication or cognitive differences. Communication may include speech, sign language, writing, letter boards, voice output devices, pictures, facial expressions, gestures, vocalizations, and behavior. Supported decision making is a paradigm, support practice, and emerging legal structure that focuses on assisting patients with communicating their wants and needs as an alternative to guardianship or power of attorney. When establishing care, it is critical to get a detailed history of baseline traits and characteristics in the areas of cognition and communication; neuromuscular function; sensory function such as vision, hearing, and sensory processing; seizure threshold; mental health; and behavior. In general, guidelines for age-appropriate health maintenance in the general population should be followed unless the risk outweighs the benefit for an individual patient. With accurate diagnosis, psychiatric conditions can be treated effectively with the same medical, behavioral, and therapeutic modalities used in the general population. Just like any patient, those with developmental disabilities should have access to a full range of life-sustaining, curative, and end-of-life services.