OBJECTIVE: To gain detailed understanding of influences on smoking behaviour in Bangladeshi and Pakistani communities in the United Kingdom to inform the development of effective and culturally acceptable smoking cessation interventions. DESIGN: Qualitative study using community participatory methods, purposeful sampling, one to one interviews, focus groups, and a grounded approach to data generation and analysis. SETTING: Newcastle upon Tyne, during 2000-2. PARTICIPANTS: 87 men and 54 women aged 18-80 years, smokers and non-smokers, from the Bangladeshi and Pakistani communities. RESULTS: Four dominant, highly inter-related themes had an important influence on smoking attitudes and behaviour: gender, age, religion, and tradition. Smoking was a widely accepted practice in Pakistani, and particularly Bangladeshi, men and was associated with socialising, sharing, and male identity. Among women, smoking was associated with stigma and shame. Smoking in women is often hidden from family members. Peer pressure was an important influence on smoking behaviour in younger people, who tended to hide their smoking from elders. There were varied and conflicting interpretations of how acceptable smoking is within the Muslim religion. Tradition, culture, and the family played an important role in nurturing and cultivating norms and values around smoking. CONCLUSION: Although there are some culturally specific contexts for smoking behaviour in Bangladeshi and Pakistani adults-notably the influence of gender and religion-there are also strong similarities with white people, particularly among younger adults. Themes identified should help to inform the development and appropriate targeting of smoking cessation interventions.