Derek Ezra joined the Liberal Party in 1936 as member of the Cambridge University Liberal Club. He served in the Army from 1939 until the middle of 1947. In that period, he joined the National Coal Bord (NCB). He was initially appointed as deputy to Val Duncan, Director of transport and overseas relations and then replaced him after a couple of years. He was involved from mid 1948 with the Coal Committee of the Economic Commission for Europe in Genève. In 1950, he represented the British coal industry in discussions regarding the Schuman Plan. When the European Coal and Steel Community was set up in Luxembourg, he was the representative of the NBC in the UK Delegation at the High Authority. Ezra was appointed chairman of the NCB in 1971 a position he held until 1982. On leaving the NCB he became involved with various industrial and financial concerns. He was elevated to life peerage as Baron Ezra in 1983.