As Leader of the Alliance Party of Northern Ireland, Lord Alderdice played a significant role in the negotiation of the 1998 Good Friday Agreement.
He was the first Speaker of the new Northern Ireland Assembly until 2004 when he was appointed to the Independent Monitoring Commission tasked by the British and Irish Governments with security normalization and closing down terrorist activity in Northern Ireland.
He has been President of Liberal International, the global federation of more than 100 liberal political parties, Chairman of the Liberal Democrat Party in the House of Lords, and a consultant psychiatrist and Senior Lecturer at The Queen’s University of Belfast.
He is currently Director of the Centre for the Resolution of Intractable Conflict at Harris Manchester College (Oxford), Chairman of the Centre for Democracy and Peace Building (Belfast) and a Clinical Professor in the Department of Psychiatry at the University of Maryland (USA).