His first official post in the union was as patrolman in the port of Baltimore in 1944. He rapidly moved up to become port agent in New York and then Director of Organizing for the SIU Atlantic and Gulf District. Then in 1947, he became chief executive officer of SIU-Atlantic Gulf Lakes and Inland Water District, at the age of 32. He held this post until his death. Paul Hall led the SIU in the General strike of 1947 when seamen won unprecedented gains in wages and conditions. He also organized key breakthroughs for the union in bringing Isthmian Lines (with 125 ships) and Cities Service Tankers (a strongly anti-union company) under the SIU banner.