The unintended consequences of smoking stigma are an important area of research. However, there has been almost a complete absence of empirical exploration of healthcare professional smoking stigma, including the processes that undergird the smoking stigma germane to healthcare professionals. The purpose of the present thesis was to address this paucity of research with three empirical studies. Study 1, a scoping review, aimed to synthesise the current state of research on the factors impacting healthcare professionals' cessation experience. Study 2 aimed to qualitatively explore the nature of healthcare professionals' smoking stigma from the perspective of healthcare professionals with lived experience. Study 3 aimed to quantitatively test the nature of smoking stigma expressed by healthcare professionals about their colleagues who smoke in a sample of Australian healthcare professionals. Study 1 identified several limitations that characterise the literature on factors impacting healthcare professionals' cessation experiences. Namely, very few studies examined the predictors of cessation by healthcare professionals, and none directly examined the processes informing the attitudes and personal and normative beliefs about their cessation. Further, it found that the relative influence of group and other contextual factors impacting their own cessation was examined even less. Although Study 1 found evidence that age and work environment factors predict quit attempt success and some evidence of tobacco smoking stigma experiences, it concluded that the literature falls short of generating findings that can inform and guide the development of behavioural change interventions sensitive to the personal and professional characterises of this population. In Study 2, a theory was derived from semi-structured interviews with healthcare professionals who were currently and formerly smoking. This grounded theory outlined crucial aspects of how this group communicatively constructed their identities within the context of their personal and professional networks, work environment, and targeted anti-smoking media campaigns. Participants discussed their smoking as a source of shame, embarrassment, and hypocrisy, and their awareness of smoking stigma. Some highlighted the anti-smoking advertisements accentuating morality in their messaging. Participants' awareness of smoking stigma potentiated several identity gaps. However, the one that emerged most frequently implicated the communal layer - specifically, group identity membership with the collective of healthcare professionals or smokers. Participants used complex cognitive, communicative, and behavioural strategies to manage group identity membership discrepancies. In the third and final study, a vignette-based survey showed that overall, Australian healthcare professionals hold moral attitudes toward smoking and people who smoke. This included their colleagues who smoke. Further, this sample of healthcare professionals stigmatised colleagues who smoke through the endorsement of negative beliefs and emotions, which have a basis in moral attitudes towards smoking. However, the professional occupation group that the stigmatised targets belonged to did not moderate the relationship between the moralisation of smoking and stigmatising judgements. Thus, my findings suggest that healthcare professionals stigmatise their colleagues who smoke regardless of the healthcare role of the smoker. The findings of the present thesis provide a foundation for further research in this under-theorised and limited considerations of the consequences concerning the stigmatisation of healthcare professionals who smoke. Further, the findings of Studies 2 and 3 can be used as a basis to inform interventions to lessen the stigmatisation of smoking amongst the healthcare professional workforce. In particular, these studies provide relevant stakeholders with a better understanding of developing smoking cessation interventions better suited to support this population whose professional roles may result in uniquely different needs.