Mutual support groups whose members are individuals who have a substance use disorder or any of a number of behavioral addictions which are akin to substance-related disorders in clinical expression, brain origin, comorbidity, physiology and treatment. The groups meet in-person, by telephone or via the Internet; provide emotional support, information and resources to help those who participate modify their behavior; and may include faith-based and secular 12-step groups as well as non-12 step groups. (AIRS PN-8100.0500)