According to South African and American researchers XDR TB (extremely drug-resistant tuberculosis; i.e. strains of TB that are resistant to isoniazid, rifampicin and three of the six groups of second line anti-tuberculous drugs) may inhibit the success of tuberculosis and HIV treatment programs worldwide. Neel Ghandi and colleagues1 reported that XDR TB poses a greater threat to low-income countries such as South Africa and that committed action is needed to address the issue of resistant strains. The study shows the devastating effect of XDR TB on patients and health workers, its alarmingly high mortality rates in those co-infected with HIV, and rapid nosocomial spread.