Before commencing his academic career in 2007, Pimentel headed the Rule of Law efforts in South Sudan for the United Nations Mission in Sudan; he has led court reform projects in Bosnia and Romania as well. He spent four years as the chief of court management at the United Nations’ International Criminal Tribunal for the former Yugoslavia in the Netherlands. He has researched and consulted on issues of judicial structure and legal pluralism in Nepal, South Sudan, Mozambique and Turkey. Pimentel spent the 2010-11 academic year as a Fulbright Scholar at the University of Sarajevo, researching the impact of post-war judicial reform in Bosnia and Herzegovina.