Castellanos was elected to a four-year term as Rector of the National Autonomous University of Honduras in 2009. At the time of her appointment as rector, she was also the Coordinator of the UNAH Violence Observatory and Director of the Instituto Universitario en Democracia Paz y Seguridad (Institute for Democracy, Peace and Security, IUDPAS). IUDPAS was started with support from the United Nations Development Programme (UNDP) and the Swedish International Development Cooperation Agency (SIDA) when Castellanos worked as a consultant for the UNDP. Castellanos took the place of Jorge Abraham Arita, who was removed for incompetence. In a press conference, College Board president Olvin Rodriguez said Castellanos was chosen as rector because she was well-respected by the university community, and also by Honduran society and internationally.