"The NBER Bulletin on Aging and Health provides summaries of publications like this. You can sign up to receive the NBER Bulletin on Aging and Health by email. Exploiting changes in welfare policy across states and over time and comparing relevant population subgroups within an econometric difference-in-differences framework, we estimate the causal effects of welfare reform on adult women's illicit drug use from 1992 to 2002, the period during which welfare reform unfolded in the U.S. The analyses are based on all available and appropriate national datasets, each offering unique strengths and measuring a different drug-related outcome. We investigate self-reported illicit drug use (from the National Surveys on Drug Use and Health), drug-related prison admissions (from the National Corrections Reporting Program), drug-related arrests (from the Uniform Crime Reports), drug-related treatment admissions (from the Treatment Episode Data Set), and drug-related emergency room episodes (from the Drug Abuse Warning Network). We find robust and compelling evidence that welfare reform led to declines in illicit drug use and increases in drug treatment among women at risk for relying on welfare, and some evidence that the effects operate, at least in part, through both TANF drug sanctions and work incentives"--National Bureau of Economic Research web site.