Focus group methodology was used to determine the barriers to smoking cessation for pregnant women prior to the commencement of a randomised controlled smoking cessation trial (RCT), using nicotine patches in the treatment arm. Attitudes to the use of nicotine patches and perceptions of care provider counselling were also explored. Women were identified by researcher interview in the antenatal clinics as current smokers or recent ‘quitters’ and recruited to one of three focus groups. A number of barriers to achieving smoking cessation were identified. Pregnancy-specific barriers included scepticism about smoking-related harms. Other barriers, such as addiction to nicotine and the smoking behaviour of others, particularly partners, are generic. The latter is magnified in pregnancy by the heightened complexities of familial relationships. Potential use of patches was acceptable to most women, although some high-risk patients expressed doubts about safety and believed continued smoking was preferable. Women recounted that care providers differed in approaches to smoking cessation. Reporting ‘cutting down’ generally avoided further inquiries about smoking. The knowledge gained of pregnant women's perspectives enhanced the researchers' understanding in these areas. These insights have been incorporated into staff training initiatives, have guided the planning of the RCT, and have continued to inform its conduct.