Managing director of the Institute of Human Rights of Catalonia (IHRC), Guillén holds a bachelor’s degree in physical sciences and a master’s in international relations. She has worked as a human rights expert for the OSCE in Kosovo and has participated in several election observation missions in countries such as Nicaragua, Ukraine, Albania, Serbia, Macedonia and Kyrgyzstan. She is specialised in international systems of protection of human rights, development cooperation and the right to the city. As a teacher, she has conducted numerous workshops on human rights and HRBA and is a consultant for the UOC in the law degree and several masters and postgraduate studies.