As one of the few legal psychoactive substances in most parts of the world and one that is also consumed for socialization and cultural and religious rituals, alcohol has historically been the most popular psychoactive substance in the world. There are, however, considerable individual and country variations in the consumption of alcohol. This chapter reviews the most recent report by the World Health Organization (WHO) based on survey data collected from 173 WHO member states concerning alcohol consumption, harm related to alcohol consumption, and policy responses to reduce the harmful effects of alcohol consumption. This chapter also examines some of the sociocultural factors that could explain the variations in alcohol consumption within country and between countries, including gender and age, the law and religion, economic wealth of individuals and society, and the culture surrounding alcohol consumption.