“…The short-term positive effects of treatment on subsequent labor force participation have been fairly well documented (Butzin, Scarpitti, Neilsen, Martin, & Inciardi, 1999;French et al, 1993;Hall et al, 2004;Kemp, Savitz, Thompson, & Zanis, 2004;Leukefeld, Webster, Staton-Tindall, & Duvall, 2007). Nevertheless, while some evidence points to the enduring nature of the improved work status resulting from criminal justice-sponsored treatment, with benefits lasting between 3 and 5 years (Butzin et al, 2005;O'Connell, Enev, Martin, & Inciardi, 2007;Sung, 2001), the lack of experimental control or the failure to control for baseline employment differences, or both, in these longitudinal studies renders their findings inconclusive and the contamination from self-selection highly plausible.…”