CONTEXT: The global tobacco epidemic may kill 10 million people annually in the next 20-30 years, with 70% of these deaths occurring in developing countries. Current research, treatment, and policy efforts focus on cigarettes, while many people in developing regions (Asia, Indian subcontinent, Eastern Mediterranean) smoke tobacco using waterpipes. Waterpipes are increasing in popularity, and more must be learned about them so that we can understand their effects on public health, curtail their spread, and help their users quit. OBJECTIVE: To conduct a comprehensive review regarding global waterpipe use, in order to identify current knowledge, guide scientific research, and promote public policy. DATA SOURCES: A Medline search using as keywords "waterpipe", "narghile", "arghile", "shisha", "hookah", "goza", "hubble bubble" and variant spellings (for example, "hooka"; "hukka") was conducted. Resources compiled recently by members of GLOBALink were used. STUDY SELECTION: Every identified published study related to waterpipe use was included. DATA SYNTHESIS: Research regarding waterpipe epidemiology and health effects is limited; no published studies address treatment efforts. Waterpipe use is increasing globally, particularly in the Eastern Mediterranean Region, where perceptions regarding health effects and traditional values may facilitate use among women and children. Waterpipe smoke contains harmful constituents and there is preliminary evidence linking waterpipe smoking to a variety of life threatening conditions, including pulmonary disease, coronary heart disease, and pregnancy related complications. CONCLUSIONS: More scientific documentation and careful analysis is required before the spread of waterpipe use and its health effects can be understood, and empirically guided treatment and public policy strategies can be implemented.