Between 1994 and 1997, Ahern served as Opposition spokesman on the Environment with special responsibility for Housing. In 1997, he served as Chairman of the Oireachtas All Party Dáil Committee on Social Community and Family Affairs. In 2002, he was appointed as Minister of State at the Department of the Environment, Heritage and Local Government, with responsibility for Housing and Urban Renewal, and at the Department of Community, Rural and Gaeltacht Affairs, with responsibility for Drugs Strategy and Community Affairs. After the 2007 general election, he was appointed as Minister of State at the Department of Finance with special responsibility for the Office of Public Works.