Official dollarization refers to the adoption of the U.S. dollar as legal tender in place of the national currency. Some Latin American countries have recently dollarized, and others have seriously considered dollarization. This article discusses the reasons behind the surge of interest in dollarization and provides a review of the new academic literature on the topic. It discusses in detail some of the factors that are commonly considered to be the important costs and benefits of dollarizing. The paper also provides an analysis of the existing liability dollarization in several countries and its relation with official dollarization. Finally, it briefly looks at dollarization from the perspective of the United States.