Joshua Castellino is Co-Executive Director of Minority Rights Group International (MRG) and Professor of International & Comparative Law at University of Derby, UK.  He founded the Law School at Middlesex University and served as Dean until 2018. At MRG Joshua engages in global research and advocacy, leading a fifty-five-year-old organization headquartered in London with offices in Kampala and Budapest, that sits at the center of a network of over 300 partner organizations implementing over 40 projects in nearly sixty countries. He collaborates with law-oriented organizations, serving as Chair of Privacy International UK, and on governing boards of the European Centre for Constitutional & Human Rights, Germany, the European Centre for Minority Issues, Germany, the European Human Rights Advocacy Centre, UK, the Institute for Statelessness & Inclusion, Netherlands and Survival International, UK. In his ex-officio MRG role he is Proprietor of Minority Rights Group Europe, Hungary, and member of the governing board of Minority Rights Group Africa, Uganda. He has advisory roles at the Sustainable Development Solutions Network, the World Economic Forum, the African Commission of Human & Peoples’ Rights, and is listed as Door Tenant at 25 Bedford Row. Joshua holds visiting academic positions at the College of Europe (Poland) & Oxford University (UK) where he teaches specialist modules on their Masters programs, and holds an honorary Adjunct Professorship in Law at the National University of Ireland (Galway, Ireland).

Born and brought up in Mumbai, India, Joshua worked as a journalist for Indian Express Group in the 1990s, before winning a Chevening Scholarship in 1995 to undertake an MA in International Law & Politics in the UK, completing his PhD in International Law in 1998. He has published eight books and over a hundred articles on international law & human rights over twenty-five years in academia, including the Minority Rights Series (Oxford University Press). He engages with questions of international law, minority and indigenous peoples’ rights at inter-governmental, parliamentary, apex courts, bar associations, civil society organizations and Universities across the globe. Joshua helped design and participated in the European Union China Diplomatic & Expert Dialogue on Human Rights (2002-2006) and was appointed Chair by the United Nations Office of the High Commissioner for Human Rights of the 8th Forum on Minority Issues (2015), an inter-governmental dialogue with civil society under the auspices of the United Nations Human Rights Council, Geneva. He has authored two new forthcoming books: Calibrating Colonial Crime (Bristol University Press, 2024) and International Law & the Reconceptualization of Territorial Boundaries: In Pursuit of Perpetual Peace (Routledge, 2025).