In INTERNATIONAL PUBLIC GOODS AND TRANSFER OF TECHNOLOGY AFTER TRIPS 393-424 (K. Maskus and J. Reichman eds.)(Cambridge Univ. Press 2005)The task of ensuring access to essential medicines presents a complex and embedded set of problems that will remain a persistent feature of the international governance landscape for the foreseeable future. The WHO’s recommended list of essential medicines has been developed with a view to aiding procurement authorities in determining the supplies needed to treat local populations. The price of medicines is a significant factor in determining what should be included on the list since there is small utility in recommending expensive therapies that are not affordable.Nonetheless, the most recent WHO Essential Medicines list includes a significant number of antiretroviral medicines (ARVs) that are under patent. These drugs may not be affordable for many HIV-positive individuals, even taking into account recent price declines, unless public health budgets in developing countries are supplemented by international assistance.The world community is presently confronted with tremendous public health challenges due to HIV/AIDS, malaria and tuberculosis. Yet, populations around the world, and especially in developing and least-developed countries, face heavy public health burdens from many sources, including other infectious diseases, diarrheal diseases, cancer, diabetes, heart and circulatory disease, and other conditions. While HIV/AIDS is the most immediate problem, it is not enough to address only this scourge.Although there has been considerable public debate concerning the effect of patents on access to medicines, ensuring adequate supplies involves an extensive regulatory framework encompassing a multiplicity of factors. These include:* Research and Development* Safety and Efficacy (including Liability)* Manufacturing Systems and Controls (Good Manufacturing Practices)* Intellectual Property * Procurement, Distribution and Dispensing* Health Care Personnel and Infrastructure* FinancingEach of these elements in the essential medicines supply chain can and does act as a roadblock. Yet, each element is present for a reason. It is not helpful to supply inexpensive medicines if they are not safe and effective, or if they are prescribed to treat the wrong condition.