Combined Task Force 151 (CTF-151) is a multinational naval task force, set up in 2009 as a response to piracy attacks in the Gulf of Aden and off the eastern coast of Somalia. Its mission is to disrupt piracy and armed robbery at sea and to engage with regional and other partners to build capacity and improve relevant capabilities in order to protect global maritime commerce and secure freedom of navigation. It operates in conjunction with the EU's Operation Atalanta and NATO's Operation Ocean Shield.