Forty episodes of invasive group B streptococcal infections in nonpregnant adults at Chris Hani Baragwanath Hospital, Soweto, South Africa, were retrospectively reviewed. The mean age of the patients was 45.6 years. Twenty (50%) patients were bacteraemic. Common predisposing conditions included diabetes mellitus (27.5%), trauma (25%), and HIV infection (12.5%). Soft tissue abscesses and pneumonia accounted for 70% of the presentations. Ten (25%) patients had acquired the infection nosocomially. Death occurred in 14 (35%) patients and was significantly associated with bacteraemia (P = 0.0009) and pneumonia (P = 0.0012). Trauma is an important predisposing condition, and HIV infection may have played a role in the setting described; both factors probably accounted for the relatively young age of the patients.