Self-help groups are part of a larger mutual aid movement. Found in many forms, the concept of peer-to-peer help is an effective, worldwide phenomenon. This chapter is concerned with single disorder 12-Step groups for chemical dependency, which have the largest participation of any other kind. There is evidence supporting the utility of 12-Step groups for alcohol and other drug dependence. Based on the principles of Alcoholics Anonymous (AA), there are now 12-Step groups for a wide range of addictions and other conditions. 12-Step groups best serve the chemically dependent as opposed to those with a diagnosis of clinical abuse. However, concerns have been raised about their appropriateness for chemically dependent people who have experienced trauma. In this chapter, 12-Step groups are discussed as to their conceptual and practical utility for chemically dependent victims of trauma.