Professor Diarmaid Ferriter is one of Ireland's leading historians. He is Professor of Modern Irish History in University College Dublin and has published extensively on nineteenth- and twentieth-century Irish history. He is the author of a number of acclaimed books on Irish history, including The Transformation of Ireland 1900-2000, Judging Dev: A Reassessment of the Life and Legacy of Eamon de Valera and Occasions of Sin: Sex and Society in Modern Ireland, and was a researcher and writer with the Dictionary of Irish Biography, 1998-9. He is also a regular contributor to RTE, anchoring the successful radio series What If? from 2006 to 2008 and authoring and presenting the television series Lovers of Liberty in 2010.