Data were obtained between 1988 and 1990 on cases in which someone had been arrested for growing marijuana in Illinois; the primary focus was on commercial marijuana growers. Newspapers were examined and letters of inquiry were sent to prosecutors and local sheriffs. Of 74 identified cases, 23 were excluded and 31 agreed to be interviewed. Marijuana growers had been in business for an average of 5 years. The largest operation had over 6,000 plants, while the median operation had 75 plants. Six of the 31 cases grew all or part of their crops indoors which made detection more difficult and allowed them to harvest crops all year. Marijuana growers included hustler, pragmatist, and communal types. Hustlers were entrepreneurs by instinct, pragmatists were driven to marijuana production by economic necessity, and communal growers cultivated marijuana as part of a larger lifestyle. The value of marijuana crops was directly related to the amount of grower effort and expertise. Although money was important, it was not the only motivating factor in marijuana production. This was particularly true for communal growers who were less likely to be driven to make large sums of money. For them, the process of growing marijuana had spiritual, social, and intrinsic rewards. Implications of the findings for policies aimed at eliminating the drug business are discussed. 21 references and 1 note