Avoidant restrictive food intake disorder (ARFID) is a rearticulated eating disorder diagnosis in the Diagnostic and Statistical Manual of Mental Disorders (fifth edition) (DSM-5), published in 2013. The purpose of this article is to review what is known about ARFID; specifically outline the DSM-5 diagnostic criteria; review the epidemiology; describe the clinical characteristics of patients with this disorder; and discuss evolving treatment approaches. Although this disorder occurs across the lifespan, the focus of recent research has been primarily in children and adolescents with ARFID. Therefore, most of this article is devoted to children and adolescents with ARFID.