 In 2000 Kristian Vigenin was elected to the Supreme Council of the Bulgarian Socialist Party and in the end of 2001 became a member of the Executive Bureau of the Party.Since 2003, he was a full member of the Socialist International and a member of the Party of European Socialists, since 2005.Following his membership in BSP, Vigenin was elected as Member of Parliament from Yambol and the same year became a member of the European Parliament.