The company, which also runs the upmarket Celebrity Cruises brand, operates eight of its 29 ships in Europe. MacGregor joins on 8 August to raise both brands' European profiles in the beefed-up post of director of corporate comms.
Previous head of corporate comms Michele Andjel left to join rival P&O Cruises in April (PRWeek, 6 March).
'My remit is reasonably broad, but it will be similar to my role at Coca-Cola,' said MacGregor. 'There is potential for selling these two brands to a wide audience.'
While Royal Caribbean appeals typically to family holidaymakers and 30 to 50-year-olds, Celebrity Cruises is a 'premium cruise line' offering luxury spas and plush onboard decor. It also employs Michel Roux as director of catering and recently ordered the world's largest cruise ship, 'Freedom of the Seas', which will carry up to 3,600 passengers.
MacGregor, who was made redundant as Coca-Cola EMEA comms manager last December, will report to Miami-based senior vice-president of comms Lynn Martenstein.