Although HIV infection rates in South Africa have been high and rising for nearly a decade, the epidemic of HIV/AIDS-related morbidity and mortality is just beginning. As South African adults start to sicken and die, concern is mounting about the potential costs to companies of HIV/AIDS among employees. When a business recognizes the threat posed by HIV among employees, it can pursue three basic response strategies for mitigating short- and long-term financial consequences: (1) try to prevent new infections; (2) avoid or reduce the costs associated with existing and future infections; and (3) provide treatment and support for infected employees to extend their productive working lives and thus postpone the costs of infection. This paper assesses the potential benefits to South African businesses of the third strategy. We describe an approach and methods for analysing the benefits of interventions that extend the working life of employees and demonstrate such an analysis using published data on the costs of HIV/AIDS to companies. The analysis indicates that the benefits to companies of investments in treatment and care are likely to exceed the costs for some existing interventions. Further work is needed to identify effective and affordable interventions, assess the benefits to companies of implementing the interventions, and bring these benefits to the attention of business and government leaders.