Dr. María Isabel Castillo Báez has been the ambassador of the Dominican Republic to the United States of America since April 2025. She has over 20 years of diplomatic experience, having joined the Dominican Foreign Service in 2002. She earned her doctor of law degree, Magna Cum Laude, from the Universidad Iberoamericana in Santo Domingo. She also holds two master's degrees from Columbia University: a master of Laws from Columbia University, where she received the Parker School of Foreign and Comparative Law Award; and a master of International Affairs from the School of International and Public Affairs (SIPA), with concentrations in Latin American and Economic Development. In addition, she completed a certificate in French civilization at the Sorbonne and studied business and international trade at Harvard University.

Before joining the diplomatic service, she worked as an intellectual property attorney at the law firms of Castillo y Castillo in the Dominican Republic, Ladas & Parry in New York City, and later at González Calvillo SC in Mexico City. From 2002 to 2005 and from 2009 to 2020, she served at the Embassy of the Dominican Republic in Mexico, gaining extensive experience in bilateral Mexico-Dominican Republic relations and leading the initiative that resulted in the creation of the Mexico-Dominican Republic Binational Chamber of Commerce. From 2020 to April 2025, she served as ambassador of the Dominican Republic to Mexico, where she was instrumental in strengthening cooperation, as well as trade and investment relations between the two countries.

Ambassador Castillo Báez has received numerous awards for her diplomatic work from various entities, including the Miguel Hidalgo Borough of Mexico City, El Dinero Magazine, the Mexican Congress, and the Atlixco Municipal Council in Puebla. She also received the 2025 Dominican Women's Medal of Merit from the Dominican government.

Currently, she is a member of the Board of Directors of the Mexico-Dominican Republic Chamber of Commerce (CABIMEX-RD) and has served as a liaison between non-governmental organizations on several social development and human rights projects, including the Chanel Foundation, Melel Xojobal AC, Go Campaign, and Yo Quiero Yo Puedo IMIFAP.

In addition to Spanish, her native language, she is fluent in English and French. She is married and has three children.