This single-volume resource provides sound, up-to-date information and authoritative resources for research on the controversial topics of the use of marijuana for medical and recreational purposes and the effects of marijuana use on society. The use of marijuana has consistently been a highly controversial, polarizing, and emotional topic, so much so that social, cultural, and religious factors have largely influenced public opinion, legislation, and law enforcement's treatment of marijuana use. At the same time, much of the scientific information about the plant has largely been ignored in the policies and practices of the United States over the past 100 years. Marijuana: A Reference Handbook provides detailed coverage of the history and background of marijuana use in society, with special emphasis on the present day in the United States. It outlines the development of federal and state legislation with respect to marijuana use over the last century, focusing on changes that are taking place in the second decade of the 21st century, and examines the pros and cons of the use of marijuana for a variety of purposes. The book presents readers with unbiased, research-based information about the effects, benefits, and risks of marijuana use. Readers will also learn about the role of hemp across human history and about very recent legislative action on the use of marijuana for both recreational purposes and medical use.