Mary is best known for her time as Chief Executive of The Royal Borough of Greenwich: 2000 to 2014. Working with Chris Roberts who was Leader at the time, she was responsible for delivering some of the largest regeneration projects in London while also not just maintaining but improving the quality of local services available to residents. In addition to this she contributed to ensuring London 2012 was a success in Greenwich and attracted the Tall Ships Race to the Royal Borough.
Prior to Greenwich, Mary was Director of Social Services and Housing London Borough of Harrow, 1992 to 2000. And at London Borough of Southwark she was Assistant Director of Social Services (Finance, Strategy and Policy),1980 to 1992. And Departmental Development Officer, 1979 to 1980.
Following her time at Greenwich Mary was appointed by central Government as a Commissioner for Rotherham Metropolitan Borough Council, 2015 to 2019. She was previously an Inspector on DCLG (Casey) Corporate Governance Inspection of Rotherham Council – November 2014 to February 2015.
In 2016 she was appointed as a non-executive director on the ministerial board of DCLG and in the 2019 New Years Honours List was made a Dame Commander of the Order of the British Empire for her services to Local Government.