Smoking remains a leading cause of premature, preventable death in South Africa killing 44 000 South Africans each year. Through the introduction of comprehensive tobacco control policies, the South African government has tried to reduce the death toll and a significant reduction in tobacco use has been recorded since its peak in the 1990’s. Smoking among women, however have remained unchanged, which calls for actions. Pregnant mothers are specifically vulnerable as their smoking detrimentally affects their own health as well as the health of their babies. This thesis gives an account of the role the antenatal care system could play in reducing the burden caused by cigarette smoking.   The overall aim was to contribute to an understanding of how a person-centred approach to smoking cessation among disadvantaged pregnant women with high smoking rates may influence smoking behaviour. The specific objectives were to confirm the high smoking rates of the target population, assess their readiness to quit, explore existing barriers and promoting factors towards smoking cessation efforts within the public antenatal health care system, and to qualitatively assess the attitudes and perceptions of disadvantaged pregnant women regarding a personcentred smoking cessation intervention.   The high smoking rates of the target population was confirmed based on a cross-sectional study at antenatal clinics in four main cities of South Africa. It focused on the prevalence of smoking during pregnancy and used the stages of change theory to identify their readiness to quit. Additional questions concerned pregnancy related disease experiences, socio-economic determinants of continued smoking as well as attitudes towards the existing clinic services and its possible role in smoking cessation. A qualitative interview study analyzed more in-depth barriers for two-way communication between pregnant mothers and midwives. Both these studies informed the design and development of a person-centred smoking cessation intervention delivered at four public sector antenatal clinics in Cape Town. The intervention was subjected to a comprehensive evaluation based on a combination of quantitative and qualitative measures. This thesis utilizes data from the qualitative process assessment part, comprising individual interviews and focus group discussions with pregnant women during the implementation period of the intervention.   The survey results pointed out a high prevalence of smoking of 46% amongst disadvantaged pregnant women, with varying readiness for behaviour change. Most women were in the contemplation stage of behaviour change and thus ready to quit. Many of the women felt positive about the role of the midwife as an antenatal care provider, but they did not have confidence in midwives concerning encouraging or supporting women to change addictive behaviour be it smoking, alcohol or other illegal substances. The qualitative research highlighted the need for revised curricula for health education and counselling. The analysis illustrated how the current situation created tension between clinic staff and pregnant women making women feel unworthy and thus leaving little room for changing behaviour. The in-depth interviews and the focus group discussions provided an analytical account of how the person-centred approach in this population was perceived by the women themselves. It illustrated that a multifaceted intervention programme, using peer counselors and educational material designed specifically for a given target population, can successfully bring about behaviour change. The intervention succeeded in shifting women’s perceptions of hopelessness into feelings of being empowered to face their addictions and competent to make a change. Though the intervention meant greater rapport with the midwives, involving peer counsellors was rated highly by the participating women. The women reported having used the educational material and attached a great value to the appropriateness of the material to their life situations, and the effectiveness of having it combined with counselling from a peer counsellor. This qualitative evaluation showed the importance of a multifaceted intervention approach, in helping women identify with their behaviour change.   The thesis highlights the importance of designing smoking cessation interventions that are specific to the needs of target populations. When smoking cessation efforts are included into routine antenatal services it is important that the target group inform the nature and specific components of the intervention.