| David Ian Jones | 4 September 2012 | |
| Goronwy Owen Roberts | October 1964 | April 1966 |
| Thomas George Thomas | 6 April 1966 | 7 January 1967 |
| Eirene Lloyd White | January 1967 | June 1970 |
| James David Gibson-Watt | June 1970 | March 1974 |
| John Stradling Thomas | 1983 | 1985 |
| Sir Ieuan Wyn Pritchard Roberts | June 1987 | 1994 |