The United States and the Netherlands have antithetical marijuana control policies. The United States' laws criminalize the possession of even small amounts of marijuana, while the Netherlands have maintained, over the past several decades, two relatively liberal marijuana policies implemented during the 1970s and 1980s. According to the literature on environmental drug prevention strategies, the Dutch policy should result in increased marijuana use because of the drug's amplified availability, while the United States' policy should result in reduced marijuana use. The empirical evidence addressing these hypotheses, however, is sparse. The stark approaches to marijuana control in the United States and the Netherlands offer the opportunity for an intricate legal and social science analysis. An examination of these divergent policies is important because it implicates, first, the extent to which marijuana, a relatively non-serious drug of abuse, is controlled, and second, the extent to which environmental drug prevention strategies are realized by policymakers in the United States and in the Netherlands. Part I of this essay examines the short- and long-term physical and psychological effects of marijuana use. Part II, first, summarizes the marijuana control philosophy in the United States, and second, examines the prevalence of marijuana use in the United States. Part III first, summarizes the Dutch philosophy on marijuana control, and second, reviews the prevalence of marijuana use in the Netherlands. Part IV discusses the implications of the American and Dutch marijuana control policies in relation to environmental drug prevention strategies.