This report examines the extent and nature of marihuana use in the U.S. It presents information on the social and psychological influences as well as the toxicological and pharmacological effects. It also analyzes effects on behavior and discusses theraputic aspects of the drug. (Author/HMV)

Data revealed a similar pattern of personality, environment, and behavior differences between all nonuser and user groups, suggesting a pervasive social-psychological constancy. The same variables were also predictive of the shift from nonuse to use over time among the high school students but not the college students. (JB)