In the past, malaria control efforts in sub-Saharan Africa have relied on a combination of vector control with effective treatment using chloroquine. With increasing resistance to chloroquine, attention has now turned to alternative treatment strategies to replace this failing drug. Some countries have already changed their official first-line treatment to sulfadoxine-pyrimethamine, while others are contemplating a switch to artemisinin-based combination treatments (ACTs). Although there are strong theoretical arguments in favor of switching to ACTs, the validity of these arguments in the face of financial constraints has not been previously analyzed. In this report, we use a bioeconomic model of malaria transmission and evolution of drug resistance to examine questions of optimal treatment strategy and coverage when drug resistance places an additional constraint on choices available to the policymaker.