The Craiova Group (Quadrilateral), Craiova Four, or C4 is a cooperation project of four European states – Romania, Bulgaria, Greece and Serbia – for the purposes of furthering their European integration as well as economic, transport and energy cooperation with one another. The Group originated in a summit meeting of the heads of governments of Bulgaria, Romania and Serbia, held on 24 April 2015 in the Romanian city of Craiova. At the group's inaugural meeting, Romania's then-Prime Minister Victor Ponta indicated that he was inspired by the Visegrád Group. Romania and Bulgaria both joined the European Union on 1 January 2007, while Serbia has been in accession negotiations since January 2014. Since October 2017 at the meeting in Varna, Bulgaria, with the inclusion of Greece, meetings have