Abstract Introduction previous research has suggested that pregnant women prefer a person-centred approach for smoking cessation interventions. However few studies have illustrated the mechanism through which such an approach has an influence on quitting or reduction rates among pregnant women in resource poor settings. Purpose to explore the role of different components included in a smoking cessation intervention delivered to disadvantaged pregnant women with high smoking rates attending public health antenatal clinics in South Africa. Methods a qualitative design consisting of focus-group discussion with women exposed to the intervention was used. Women were purposively selected from four antenatal clinics and one tertiary hospital to represent different experiences of the intervention. Focus group discussions with four groups of smokers and four groups of quitters were conducted and a total of 41 women were interviewed. Data were analysed using content analysis. Main findings the main theme describing the intervention effect that emerged from the interviews was, ‘Making identification with change possible’. The categories ‘An impulse for change’, ‘An achievable recipe’, ‘A physical reminder’ and ‘A compassionate companion’ further described how each intervention component was perceived by women and how it contributed to behaviour change. Conclusions behaviour change interventions that are directly informed by the target population with regards to its design, content and delivery offer great opportunities for positive behaviour change. Women positively evaluated all the components employed in this intervention but rated the social support they received from peer-counsellors as the overriding aspect of the intervention.