Individuals with autism spectrum disorder experience chronic-health conditions (e.g., seizures, gastrointestinal concerns) more frequently and have higher mortality rates than non-autistic peers. Challenging behavior may occur when expected to cooperate with medical providers and autistic individuals may experience anxiety related to dental or other medical procedures. This chapter describes research on strengthening cooperation to critical medical and dental procedures to promote health outcomes across the lifespan. Important topics like interdisciplinary collaboration and training for healthcare professionals are discussed and the authors describe various interventions based on respondent (e.g., systematic desensitization) and operant (e.g., shaping, noncontingent reinforcement) conditioning to help support individuals with autism during critical medical care.