In this study, we investigate the movements of the nominal effective exchange rates (NEER) of East Asian currencies and the Asian Monetary Unit (AMU), which is the weighted average of East Asian currencies, during the course of the global financial crisis. We found that the NEER were more stable in countries that adopted the currency basket system even during the financial crisis. Comparisons made between the NEER and a combination of the AMU and AMU Deviation Indicators show intra-regional exchange rates among the East Asian currencies, and that there have been strong relationships between them before and after the global financial crisis. Accordingly, monitoring both the AMU and the AMU Deviation Indicators is effective in stabilizing the NEER of East Asian currencies. In this respect, our findings indicate that the AMU Deviation Indicators as well as the AMU will play a very important role in the surveillance of the stability of intra-regional exchange rates.