This paper investigates the consequences of Basel II for international capital flows to emerging markets. The paper shows that the magnitude of effects critically depends on a number of assumptions, including: the mapping of risk weights to ratings, assumptions about required return on capital, assumptions about competition and diversion effects and the assumption that minimum capital requirements are binding constraints. The paper provides evidence on each of these assumptions and estimates their effect on interest margins and bank flows. Overall the results suggest that Basel II — taking into account the "Potential Modifications" of November 2001 - will have only a moderate impact on international capital flows.