With the increasing complexity of modern medical therapies, it is becoming imperative to recognize the marginal cost and gains of increasingly sophisticated (and expensive) interventions. By understanding the incremental cost of a given intervention, investigators must help answer questions about healthcare resource utilization that are not answered by randomized clinical trials. The continued funding of biomedical research and pharmaceuticals will require more objective study of the return on investment for any given treatment modality, and cost-effectiveness analyses will be instrumental in providing solutions to the inequalities in healthcare delivery.