INT’L. J. SELF HELP & SELF CARE, Vol. 4(3) 239-255, 2005-2006 THE EFFECTS OF TWELVE-STEP PARTICIPATION ON SOCIAL SUPPORT: A LONGITUDINAL INVESTIGATION WITHIN A RECOVERY HOME SAMPLE* DAVID GROH LEONARD JASON JOSEPH FERRARI JANE HALPERT DePaul University ABSTRACT Mutual-aid/12-step involvement has been found to relate to numerous positive facets of social support. However, this present investigation is the first known study to longitudinally assess the influence of 12-step involvement on social support within a U.S. Oxford House recovery home sample (N = 897). As predicted, AA/NA attendance predicted social net- works containing more general social support over a 1 year period, and it is recommended that individuals in recovery lacking positive social support might turn to 12-step groups to develop these necessary forms of support. However, 12-step participation failed to predict network drinking behaviors or support for drinking. Although counterintuitive, it is possible that 12-step groups impact general support more than recovery-specific types of support. It is true that more of AA’s 12 steps deal with mending relationships than alcohol use. *Portions of this article were taken from the doctoral dissertation of the first author. The authors appreciate the financial support from the National Institute on Drug Abuse (grant number DA13231). 239 Ó 2009, Baywood Publishing Co., Inc. doi: 10.2190/SH.4.3.e http://baywood.com