Ms McGivern began her career as a teacher in further education. In the 90s, she moved to develop policy for the youth service in Northern Ireland and in 1995 joined the Civil Service in the Urban Regeneration Initiative. In 1999 she joined the Belfast City Council as Director of Development heading up a newly-created department combining the economic development, arts and tourism activities of the Council with the physical development and management activities.
Most recently, in November 2009, she became Principal and Chief Executive of Belfast Metropolitan College, the biggest further education college in Northern Ireland. The College has a staff of 1,600 with 30,000 students.
Marie-Thérèse was appointed as visiting professor in the Faculty of Engineering and the Built Environment at the University of Ulster, is a Board member of the British Urban Regeneration Association, an honorary member of the Royal Society of Ulster Architects, QUB Students Union Management Board member and a member of the NI Committee of the IOD.