Problems with the quality of medicines abound in countries where regulatory and legal oversight are weak, where medicines are unaffordable to most, and where the official supply often fails to reach patients. Quality is important to ensure effective treatment, to maintain patient and health-care worker confidence in treatment, and to prevent the development of resistance. In 2001, the WHO established the Prequalification of Medicines Programme in response to the need to select good-quality medicines for UN procurement. Member States of the WHO had requested its assistance in assessing the quality of low-cost generic medicines that were becoming increasingly available especially in treatments for HIV/AIDS. From a public health perspective, WHO PQP's greatest achievement is improved quality of life-saving medicines used today by millions of people in developing countries. Prequalification has made it possible to believe that everyone in the world will have access to safe, effective, and affordable medicines. Yet despite its track record and recognized importance to health, funding for the programme remains uncertain.