 In 1950 he was elected Secretary of the Staff Side of the Magistracy Division of the Civil Service and followed that in 1955 by being elected to the Executive of the Civil Service Association(CSA) representing the Eastern Counties.He became the Assistant Secretary of the CSA in 1960 at a time when Hugh Harris was the President and O. E. Morle the Secretary.The CSA appointed Manswell as it first full-time General Secretary in 1961.