Once a grower learns the technique of indoor cultivation, he or she can produce three to four harvests in a 12-month period. The price of indoor marijuana is about $300 an ounce. Since 1992, the San Diego Integrated Narcotic Task Force has brought aggressive enforcement to indoor cultivators and has identified, apprehended, and successfully prosecuted over 30 indoor operations and seized more than 4,000 high quality marijuana plants. Investigations in San Diego have produced expertise that may help other police departments identify and build cases involving indoor marijuana growers. Once information is received about a potential grower, the investigation begins by corroborating that information. Initial information may be from a confidential informant who has actually seen marijuana plants growing or from someone who is suspicious about a neighbor. Next steps in the investigation include target assessment, determining the amount of electrical consumption, trash inspection, and obtaining and serving a search warrant. The collection of evidence is a critical part of the investigation. 2 photographs and 3 illustrations