Emer Anne Costello (née Malone; born 3 September 1962) is a former Irish Labour Party politician who served as a Member of the European Parliament (MEP) for the Dublin constituency from 2012 to 2014, Lord Mayor of Dublin from 2009 to 2010 and a Dublin City Councillor for the North Inner City area from 2003 to 2012. She is from County Louth, and has a B.A. and a H.Dip. in Education from University College Dublin. Her sister is former Senator Mary Moran.