ON PHYSICIAN MIGRATION DENSITY VICTOR KOLADE, University at Buffalo 25 June 2007 I read Dr Arah’s description of physician migration  with interest and am grateful for the introduction of the physician migration density as a measurement tool. Most striking is the observation that migration is positively associated with lower official development assistance for health. This report is therefore pertinent in that it points out what source countries can do to stem migration and improve local physician supply: find ways to improve healthcare funding. The study of South Africa as both a source and a destination country appears incomplete without an analysis in Table 1 of which nations are its source countries. It may be useful to determine how the pattern of migration to South Africa compares to patterns described for the United States, United Kingdom, and Canada.1. Arah OA: The metrics and correlates of physician migration from Africa. BMC Public Health 2007, 7(1):83. Competing interests I am a US-born Nigerian medical graduate.