Sharp, a lawyer with a background in arbitration was said to be regarded as an old friend by Cameron. When a New Ministry was announced, and his Minister"s role was expanded to include immigration, Sharp"s role too expanded and he was made Secretary of the new Department of Labor and Immigration. When Sharp handed over his Secretary position to Peter Wilenski in 1975, he spent three months with Wilenski in something of an "apprenticeship" role, sharing authority in the Department, before leaving in March that year.
On 31 March 1975 Sharp started a three-year appointment as a judge of the Australian Conciliation and Arbitration Commission.