The purpose of this study is to test for the sustainability of current account in 18 developed and 10 developing countries. The stability of the relationship between export (inflows) and import (outflows) is assessed using the tests proposed by Mohitosh Kejriwal and Pierre Perron (2010). In particular, the nature of the long-run relationship, when multiple regime shifts are identified endogenously, is analyzed using the residual-based test of the null hypothesis of cointegration with multiple breaks proposed by Kejriwal (2008). The results clearly indicate that, for all countries, (i) the stability tests reject the null of coefficient stability of the long-run relationship between exports and imports; (ii) the cointegration tests that correspond to the number of breaks selected reject the null of cointegration (weak form of sustainability); and (iii) the strong form of sustainability hypothesis is not supported by the data for all countries in most regimes but not for 20 of 28 countries especially in the last regime (the post 2000 era). For eight countries (Canada, New Zealand, Spain, Brazil, Mexico, South Africa, Thailand, and Turkey), the findings may be perceived as a warning to creditors and policymakers unless there are policy distortions or permanent productivity shocks to the domestic economies.