This paper makes an empirical contribution to discussion of the optimal exchange rate regime. Using a new dataset for Central American countries, we compare the dynamics of the real exchange rate (RER) between dollarised and non-dollarised countries. Our results show that the two dollarised countries in the region, El Salvador and Panama, are quite different in terms of RER dynamics. In El Salvador the RER spends more time away from its equilibrium level than in the non-dollarised countries in the region, while the contrary is true for Panama. We also find that inflation persistence is similar in El Salvador to the other countries, but smaller in Panama. This leads us to the conclusion that some degree of exchange rate flexibility helps countries to have a more aligned RER. Nevertheless, a long-lived, highly credible dollarised economy, like Panama, can reduce inflation persistence to such an extent that RER misalignments are in fact less frequent than in countries with more flexible exchange rate regimes.