A generally accepted view is that it is more efficient and ethical if global pharmaceutical prices vary according to countries' relative income. To understand manufacturers' pricing strategies, we compared average pharmaceutical prices in fourteen middle-income countries to those in three high-income countries and a low-income region in western Africa from 1999 through 2008. We found that some middle-income countries pay more for pharmaceuticals than high-income countries--for example, prices in several middle-income countries exceeded those in the United Kingdom for some years of the study period. Other middle-income countries paid less than low-income countries--for example, average prices in India were consistently below prices in western Africa. These variations suggest that we need new policies on pharmaceutical pricing to improve access to pharmaceuticals around the world.