Herzog was a Member of Knesset from 2003 until June 2018. From 2013 till July 2017 he was leader of HaAvoda. From 2015 till July 2017 he was also leader of HaMahaneh HaTziyoni ("The Zionist Union"), together with Tzipi Livni of HaTnu'a (still leading). Because the new HaAvoda leader Avi Gabbay is not a Knesset member, Herzog remained leading in the Knesset and leader of the Opposition.