| Title | Chairman, Board of Guardians |
| Start Date | 2009-12-18 |
| Is Current | yes |
| Board member | yes |
| Notes | Mr Costello was first appointed to the Board with effect from 18 December 2009. Mr Costello was appointed acting Chairman on 11 January 2014 and Chairman with effect from 4 February 2014 for a five-year term. He was reappointed as Chairman for another five-year term with effect from 4 February 2019. |