This research aims to examine the exchange rate regimes of 12 MENA countries. The sample is composed of the 6 GCC oil exporting countries, most of which have pegged their currency to the US dollar, and another 6 Arab countries that have different exchange rate regimes. The objective of the study is to determine the extent of over and undervaluation of these MENA currencies. The results show that official peg to the US dollar does not reduce the amount of deviation from the equilibrium exchange rate. Also, countries which had their currency pegged to a basket of currencies had lower currency fluctuations than others ...