During in-take, the New York Department of Correctional Services attempts to identify those inmates with substance abuse problems. This report presents this self-report data, and also offers data spanning the years 1996 through 2001 for comparison purposes. According to the report, 64 percent of all inmates who were in custody on December 31, 2001, were identified as substances abusers. Sixty-four percent of male inmates and 81 percent of female inmates reported abusing drugs. Nineteen percent of all inmates claimed to only abuse alcohol, while 23 percent reported using cocaine, and 28 percent reported using marijuana. Data about substance abusers is also offered by type of commitment offense and region of commitment offense. Additional demographic information on substance users is also offered, such as substance abuse by race or ethnicity and education level. Data is presented that compared the population of inmate substance abusers to the population of inmates who did not abuse substances. Recent trends for identified substance abusers is offered for the years 1996 through 2001.