This paper develops several indicators to measure the extent and depth of rules governing international migration. It is set in the context of moves towards further liberalisation of services trade and associated labour mobility (Mode 4) under GATS and related regional trading arrangements. Ten Southeast Asian countries at various stages of economic development are examined as a case study, with special reference to health care and information technology. These sectors are priority sectors for regional cooperation in services trade in ASEAN, but were expected to represent opposite extremes in terms of the regulation of migration. The study finds that the more advanced countries tend to have more liberal regimes for international movements of skilled manpower, although there were smaller differences regarding general visa and work permit arrangements. Generic restrictions on mobility were related to trade policies, as well as to direct barriers (often country-specific) to migration. They included minimum salary requirement, levies on foreign workers, economic needs tests, and limitations related to language, education and job experience. Controls were more extensive in the health care sector, related to social considerations as well as professional organisational interests.