 He was the Secretary General of the Fédération internationale de droit européen 2000–2002, the Hon Secretary of the UK Association of European Law 1997–2008 and the Hon Secretary of the UK Committee of Comparative Law 1999–2005.He was the Chair, Association of Human Rights Institutes in 2008.Since 2009 Andenas has been a member of the UN Working Group on Arbitrary Detention.