The international migration of skilled health workers has increased significantly from the 1990s. Many source countries have expressed concern over losses of health workers, resulting in regional Codes of Practice and bilateral Memoranda of Understanding being established since 1999 to achieve more effective, equitable and ethical international migration. The finalisation of a Global Code in 2010 drew attention to continued migration concerns. Codes have three key objectives - protecting rights of migrant workers, adequate workplace support for migrant workers and ensuring that migration flows do not disrupt health services in source countries. There is no agreed definition of ethical international recruitment, and no consensus on the significance and location of harmful recruitment practices. Most codes have covered relatively few regions and exhibit a high degree of generality. Several source countries encourage rather than discourage migration. Migration is a right and occurs in contexts that do not necessarily involve health issues. There are no incentives for recipient countries and agencies to be involved in ethical international recruitment. All codes are voluntary which has restricted their impact. Substantial migration and recruitment have occurred outside their scope, and codes have diverted skilled health workers beyond regulation. The private sector is effectively excluded from codes. Bilateral agreements and memoranda have a greater chance of success, enabling managed migration and return migration, but are more geographically limiting. The most effective constraints to the unregulated flow of skilled health workers are the production of adequate numbers in present recipient countries and provision of improved employment conditions in source countries.