In August 2003, she entered the Miss Ireland finals in Dublin, and winning the competition, found herself competing for the title of Miss World. December 2003 saw Davison, along with 106 other contestants, compete in the Miss World competition in Sanya, China. Rosanna went on to win the crown and is the first Irish entrant ever to win the Miss World title since it started in 1951. During Davison's reign, she travelled to the United Kingdom, the United States, Canada, China, Sri Lanka, Germany, South Africa, Ghana, Mauritius, Nigeria, Barbados, Indonesia, Poland and her native Ireland.
