During her career, Ms. Whelan has served in various capacities, among them: Ambassador to the Netherlands (2009-2014); Director General, Promoting Ireland Abroad Division at the Headquarters (2006-2009); Permanent Representative to the United Nations, Geneva (2001/2006); Director General, Director of Campaign for UN Security Council seat, Department of Foreign Affairs DFA (1998-2001); Director General, Administration and Consular Services Division, DFA (1995-1998); Counsellor, Political Division, United Nations and Middle East, DFA (1994-1995); Seconded to the Department of Trade & Tourism (1993-1994); Counsellor, Economic Division/Foreign Earnings, DFA (1991-1993); First Secretary, Anglo-Irish Division, DFA (1990-1991); First Secretary, Permanent Mission of Ireland to the United Nations, Geneva (1985-1990); First Secretary, Personnel Section, DFA (1981-1985); First Secretary, Political Division, DFA (1976-1981); Third Secretary, Embassy of Ireland, Washington (1974-1976), Third Secretary, DFA (1973).

While acting as Ireland's Ambassador to Austria she has also been appointed The new Permanent Representative of Ireland to the United Nations Industrial Development, Vienna.

She holds a Master's Degree in International Contemporary History from the New University of Ulster in Coleraine, United Kingdom and a Master's Degree in Strategic Management from the Trinity College Dublin, Ireland.