After only six months, David Gittings has resigned from his position as the FSA's director of its insurance firms division.
He has left the FSA to join the board of Wellington Underwriting as director responsible for risk management, group legal services and human resources. He takes on his new role on 16 September.
His resignation came as a shock after he made the highly-publicised move from head of Lloyd's regulation committee in April this year.
It is understood Gittings was tempted by a high-salaried position back in the private sector.
He had been working closely with the FSA's John Tiner on the Tiner Project and has been instrumental in reforming FSA regulation of the insurance industry.