The role of RDTs and decisions in their implementation In sub-Saharan Africa, management of febrile patients is typically characterized by over-prescription of anti-malarial drugs, as clinicians often do not have access to, or do not request, laboratory testing before prescribing anti malarials. Such practices were accepted, and even encouraged, when older, more affordable antimalarial such as chloroquine and sulphadoxine-pyrimethamine were effective. However, now that parasite resistance necessitates the introduction of new regimens such as artemisinin combination therapies (ACTs), the strategy of presumptive treatment has become more problematic, as the new drugs are significantly more expensive and their safety profiles are not fully characterized. Use of rapid diagnostic tests (RDTs) to guide anti malarial therapy is increasingly advocated as a potentially safe and cost-effective strategy for fever case management. Rapid diagnostic tests (RDTs) for malaria are increasingly being considered for routine use in Africa. However, many RDTs are available and selecting the ideal test for a particular setting is challenging. The appropriateness of RDT choice depends in part on patient population and epidemiological setting, and on decision makers' priorities. The model presented (available online) can be used by decision makers to evaluate alternative RDTs and assess the circumstances under which their use is justified on economic grounds.