Introduction: Tobacco smoking continues to raise serious concerns for health promotion practitioners and health bodies globally. It has been tagged the single largest cause of all premature deaths globally. Efforts at discouraging tobacco use especially among the youth are not only aimed at reducing smoking prevalence in the short term but at disrupting the chain of supply for the tobacco marketers who see the youth population as their source of replacement smokers. Measures to curb smoking prevalence currently rely heavily on policy regulation but there is need to have a holistic approach towards finding out what influences the youth to smoke in order to have relevant context-specific interventions to further tobacco control efforts. This study is aimed at ascertaining the risk influences for smoking behaviour amongst the youth in Southern Nigeria with specific focus on cultural/environmental, interpersonal and intrapersonal factors serving to increase smoking initiation and perpetuation as guided by the Theory of Triadic Influence (TTI). Method: Exploratory mixed methods research design was employed in carrying out this study. Qualitative interviews were conducted with 27 persons in 24 individual interviews (comprising of 18 young smokers aged 18 to 24 years, 4 political analysts and 2 community leaders) and 1 focus group discussion with 3 community leaders. A total of 550 youth aged between 18 and 24 years participated in the survey (quantitative) phase of this research. Non-probability sampling was used in recruiting participants for this study. Purposive sampling was used for the qualitative phase while multi-staged convenience sampling was used in the survey phase. Interpretative phenomenological analysis (IPA) with the aid of the software Nvivo 9 was used in analyzing the qualitative data while the software Statistical Package for the Social Sciences (SPSS) version 19 was used in the analysis of the quantitative data. Results: Qualitative and survey results show that there are an array of factors at various levels influencing the youth in southern Nigeria to view cigarettes as attractive and less harmful. At the cultural environmental level, there exist traditional practices in some parts of Southern Nigeria that make cigarettes easily accessible to the youth. Contact with cigarettes as a minor was found to be the best predictor of smoking among other cultural factors involving tobacco use while exposure to second hand smoke was the best predictor of smoking. With an absence of a functional national tobacco control law presently, cigarette is cheap, easily accessible to young people and tobacco manufacturers and marketers still promote their businesses in many ways which target the youth. At the interpersonal level, youth were influenced majorly by their peers to initiate smoking but indirectly by parents, older sibling and role models who smoke. At the intrapersonal level, youth were found to smoke for a variety of reasons ranging from wading off depression, coping with social stress and wanting to live up to the expectations of friends. Youth’s knowledge about the effect of smoking on health and well-being did not translate to a desire to quit smoking. Conclusion/recommendations: The Nigerian government needs to take urgent steps to address the tobacco question in the country through policy formulation and implementation. There is need to raise more awareness in the population on the dangers of smoking. Cessation clinics are also needed to help those who desire to quit smoking. Cultural activities involving the use of cigarettes and other tobacco products need to be properly addressed through the right channel to ensure this practice is stopped. A theoretical model explaining the risk influences for smoking among the youth is presented and suggestions are made with regards to a re-categorization of constructs in the theory of triadic influence which guided this study. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2013.