Data from the 1978-79 Rand Inmate Survey of convicted inmates in 12 prisons and 14 County jails in California, Michigan, and Texas are described to provide a basis for examining the characteristics of drug dealers. The self-reported information covers background sociodemographic characteristics, use of drugs, and drug dealings prior to arrest. Measures of criminal preferences and motivations for engaging in crime are developed through questions in categories concerning attitudes about crime and the criminal justice system and categories concerning the payoff from crime, specifically the economic, social and psychological benefits. Some of these measures in particular present crime as an entrepreneurial activity. Lastly, the analysis expands the conventional economic model of criminal activity to include impacts of criminal perceptions and expected returns to work and crime on both employment and drug selling.