Autism is a lifelong neurodevelopmental condition that affects approximately 1 in 31 US children and 1 in 45 US adults; autism spectrum disorder includes a wide range of neurologic diversity, symptoms, challenges, strengths, and abilities. The Diagnostic and Statistical Manual of Mental Disorders, 5th ed., text revision criteria for autism spectrum disorder require deficits in three areas of communication and social interaction across multiple settings, with at least two restricted or repetitive behaviors, not explained by another condition, and causing functional impairment. The American Academy of Pediatrics recommends screening for autism at ages 18 and 24 months in addition to routine developmental surveillance, whereas screening in adults is not recommended. Diagnosis should include a multidisciplinary team and a multidimensional assessment. Autistic individuals have a 20- to 30-year lower life expectancy than nonautistic people and experience higher rates of many chronic conditions, such as diabetes, epilepsy, gastrointestinal concerns, feeding disorders, and mental health disorders (eg, attention-deficit/hyperactivity disorder, depression, anxiety, schizophrenia). Treatment of children with autism spectrum disorder focuses on minimizing core deficits, maximizing functional independence, and preventing problem behaviors. Pharmacologic therapy may be indicated for related conditions or symptoms, such as sleep disorders, seizures, mental health conditions, behavior problems, and gastrointestinal issues. Melatonin effectively reduces sleep symptoms and improves daytime behaviors with minimal adverse effects. The SPACE (sensory, predictability, acceptance, communication, empathy) framework provides specific interventions that make health care more accessible and affirming to autistic patients.