Prolonged diagnostic and treatment delays, particularly in settings experiencing concomitant human immunodeficiency virus (HIV) and tuberculosis (TB) epidemics, undermine global TB control efforts. Current TB control policy in South Africa, as organized through the National TB Control Programme (NTP), relies on the voluntary presentation of TB suspects to local clinics for diagnosis, i.e. passive case finding (PCF). In 2005 a participatory study suggested that popular interpretation and perception of TB within eight South African township sites in and around Cape Town, all carrying a high burden of HIV and undiagnosed TB, undermine PCF. Both people's association of TB with dirt and squalor, and the anticipation of HIV-related stigma, combine to impede TB diagnosis. Respondents conveyed TB as unavoidable; this perception is expressed in the context of vulnerability where so much-including dirt-is largely beyond the control of local residents. The lack of control has a disempowering effect, reducing the drive for seeking treatment. In addition, low confidence in patient confidentiality and anticipated HIV-related stigma act as direct deterrents to TB diagnosis and treatment. In conclusion, we wish to draw attention to high levels of disease stigma and vulnerability, and how these undermine PCF. Public health interventions that wish to improve case detection should aim to: (1) emphasize how early treatment improves outcome and can curb ongoing transmission; (2) combat a sense of communal vulnerability to TB; (3) address anticipated HIV-TB stigma; and (4) improve the quality of care provided at local diagnostic services, addressing low levels of patient confidentiality.