2016 - 2018 - Mark Newman

2015 - 2016 - Lynne McQuitty

2012 - 2015 - Peter McMahon

2011 - 2012 - Lynne McQuitty

2010 - 2011 - Fiona McCusker

2008 - 2010 - Lynne McQuitty

2007 - 2008 - Karen Flanagan

2002 - 2007 - Fiona McCusker

1999 - 2002 - David McMillan

1997 - 1999 - Dr. J. R. P. Hanna

1995 - 1997 - William K. McClean

1993 - 1995 - Dr. R. J. Millar

1991 - 1993 - Michael P Cruise

1990 - 1991 - Dr. Richard J Millar

1988 - 1990 - Noel McKeown

1986 - 1988 - J Brian Burrows

1982 - 1986 - David T Beattie

1979 - 1982 - Terence K Sloan

1975 - 1979 - William F Heron

1973 - 1975 - John J McCloy

1959 - 1975 - Robert Cordner