Parent Management Training Oregon model (PMTO) is a manualized set of procedures designed for parents of antisocial children (Bank, Rains, & Forgatch, 2004; Forgatch, 1994). Three randomized trials for small samples of clinical referrals showed the training was effective (Patterson, Chamberlain, & Reid, 1982; Walter & Gillmore, 1973; Wiltz & Patterson, 1974). The effects were further replicated in randomized trials with chronic offending delinquents (Bank, Marlowe, Reid, Patterson, & Weinrott, 1991). Chamberlain (1990) and Eddy, Whaley, and Chamberlain (2004) applied PMTO techniques to randomized trials for chronic offenders in foster care settings. The procedures were also adapted for randomized trial prevention studies involving preadolescents at risk for substance use (Dishion, Patterson, & Kavanagh, 1992), recently divorced mothers (Forgatch & DeGarmo, 1999), stepparent families (Forgatch, DeGarmo, & Beldavs, in press), and families living in high crime areas (Reid, Eddy, Fetrow, & Stoolmiller, 1999). One of the unusual features of the PMTO approach is that it is tied to a theory about the causes of aggression (Patterson, 1982; Reid, Patterson, & Snyder, 2002). The theory includes a specification of the measurement models that describe the contributions of parents, siblings, and peers in determining a wide spectrum of child outcomes (Patterson, Reid, & Dishion, 1992). Recent studies used randomized prevention and intervention trials to provide experimental tests of the causal status for the key mechanisms (Chamberlain, Fisher, & Moore, 2002; Forgatch & DeGarmo, 1999, 2002). Recent studies have also introduced some interesting developments in the underlying theory. These, in turn, point to the need for modifications in the intervention. This report summarizes the recent innovations together with some targeted areas of change. (PsycINFO Database Record (c) 2012 APA, all rights reserved)