The primary function of this contract is to provide materials to support research on marijuana abuse, its effects on psychological and physical development and its potential medicinal use. It was recognized long ago that such studies require a source of cannabis material and its dosage forms such as marijuana cigarettes with consistent and predictable potency, free of contamination and in amounts to support a wide variety of research needs. Such production was established in the late 1960's by the government and this contract is a continuation of that effort. Preparations of cannabis needed for research are mostly classified under the Controlled Substance Act and therefore not available commercially. The National Institute on Drug Abuse has been providing the scientific community with standardized preparations of cannabis, cannabinoids and other drugs of abuse for basic and clinical research through its drug supply program. This contract consolidates production of cannabis and manufacture and distribution of cigarettes. The production, manufacture of cigarettes, and distribution of plant materials and cigarettes require analyses of both growing and stored materials to determine optimum harvesting time, formulation aspects, potency, content uniformity and stability. The purpose of this contract is to obtain, prepare, test, and provide cannabis preparations of marijuana cigarettes of various strengths, placebos, and bulk marijuana to investigators in drug abuse and related research.