OBJECTIVES: To study the diversity and sociodemographic characteristics of tobacco use in Bombay, India. DESIGN: Population-based, cross-sectional, house-to-house survey with face-to-face interviews in the city of Bombay during 1992-94. Data was input directly into a programmed, handheld computer (electronic diary). PARTICIPANTS: Permanent residents of the city of Bombay aged 35 years and older. MAIN OUTCOME MEASURES: Tobacco use in various smoking and smokeless forms. RESULTS: 99598 individuals were interviewed (60% women, 40% men). Among women, prevalence of tobacco use was high (57.5%) but almost solely in the smokeless form. Among men, 69.3% reported current tobacco use and 23.6% were smokers. The most common smokeless tobacco practice among women was mishri use (44.5% of smokeless users) and among men betel quid with tobacco (27.1%). About half of smokers used bidi and half smoked cigarettes. Chewing areca nut without tobacco was rare (< 0.5% of smokeless users). Educational level was inversely associated with tobacco use of all kinds except cigarette smoking. CONCLUSIONS: The pattern of tobacco use varies across India and, in Bombay, is very different from other areas. Using handheld computers to collect data in the field was successful.