This document outlines the set of agreed guiding principles for the quality assurance of essential medicines and other health care commodities, which donors will require of countries, bilateral, multilateral and third- party procurers when they use donor funds to purchase essential medicines. These agreed guiding principles would help ensure consistency in requirements for quality standards of essential medicines procured with donor funding and will provide uniformity in the application of these standards. These principles have important considerations, including that manufacturers who invest in assuring that their products meet international quality standards are not disadvantaged but are instead incentivized to remain in these markets.