The order of seniority of Government Ministers is determined by the order in which their names appear in the Dáil motion nominating them for appointment and this in turn is determined by the Taoiseach, at his discretion, usually but not necessarily by reference to length of previous Ministerial service and service in the Dáil. A copy of the current order of seniority, which was prepared in accordance with this precedent and which has been made available for reference as indicated in the question, follows:
Members of the Government
Mr. Charles J. Haughey Taoiseach and Minister for the Gaeltacht
Mr. Brian Lenihan Tánaiste and Minister for Defence
Mr. Gerard Collins Minister for Foreign Affairs
Mr. Albert Reynolds Minister for Finance
Mr. John P. Wilson Minister for the Marine
Mr. Michael O'Kennedy Minister for Agriculture and Food
Mr. Desmond J. O'Malley Minister for Industry and Commerce
Mr. Bertie Ahern Minister for Labour
Mr. Bobby Molloy Minister for Energy
Dr. Michael Woods Minister for Social Welfare
Mr. Ray Burke Minister for Justice and Minister for Communications
Mr. Pádraig Flynn Minister for the Environment
Dr. Rory O'Hanlon Minister for Health
Mrs. Mary O'Rourke Minister for Education
Mr. Séamus Brennan Minister for Tourism and Transport