This study simulated five strategies for antiretroviral treatment (ART) to assess the optimal resource allocation for ART in developing countries. The authors concluded that in the absence of second-line ART, the CD4 strategy is a more cost-effective laboratory testing strategy for managing HIV infection than either total lymphocyte count (TLC) or viral (VL). Availability of second-line ART plus CD4 cell count and/or VL measurement would save additional lives, but at high incremental cost.