After reading Anglo-Saxon, Norse and Celtic at Cambridge, Harriet Devlin worked at the Museum of London, before becoming a Museum Consultant. She moved to Northern Ireland in 1990 and worked for the Ulster Architectural Heritage Society where she compiled volumes of Buildings at Risk, a Directory of Funds for Historic Buildings and a Directory of Traditional Skills, and organised international conferences on heritage issues.
In 2000 she established the Mourne Homesteads project - using diverse funding to conserve and reuse vernacular buildings linked to skills training. Whilst in Northern Ireland, she was a member of the Historic Buildings Council, and ran a Townscape Heritage Initiative scheme as a volunteer.
On returning to England, Harriet worked for Oswestry Borough Council administering their Townscape Heritage Initiative and established a Building Preservation Trust, to restore a Welsh non-conformist chapel.
In 2005 she received a Winston Churchill Travelling Fellowship to study Preventative Maintenance schemes in Europe. Since 2005 Harriet has been running the postgraduate course in Historic Environment Conservation at the Ironbridge Institute.