Mariano Guillén-Oquendo Martínez worked in cooperation with and on the improvement of administrations and public policies since the end of the 20th century. He has worked at the Fundación Internacional y para Iberoamérica de Administración y Políticas Publicas (FIIAPP) since 2009, almost always in the field of justice. He has directed public technical assistance areas since 2014, and specifically in the Justice area since 2016. Has a degree in Law from the University of Castilla La Mancha and has been a Lawyer with the Illustrious Madrid Bar Association since 2014. He also has an undergraduate, postgraduate studies, and doctorate in various Spanish, Belgian, and English universities (University of Leeds, IESE, UNED, Université Saint Louis).

Mariano Guillén-Oquendo Martínez will participate in the World Justice Forum working session Launch of the Ibero-American Alliance for Access to Justice