Ronan O'Rahilly is an Irish businessman best known as the founder of pirate radio station Radio Caroline which broadcast from a ship anchored in international waters off the coast of Essex, southeast England .

Prior to his involvement with Radio Caroline, O'Rahilly ran a nightclub in London's Soho district and managed a number of pop music artists including Georgie Fame. He recorded a Georgie Fame record on his own independent level, unheard of at the time. He took the record to the BBC to try to get it played. He discovered that the record industry was dominated by EMI and Decca. He then tried to get it played on Radio Luxembourg. Again here, EMI and Decca, with a smaller Pye and Phillips show. He said "I have recorded the guy, so I can't get it played, so we have to start a radio station." He later became involved in the production of a number of films, including Executive Producer on the Marianne Faithfull film, Girl on a Motorcycle.

O'Rahilly was the manager of 007 actor George Lazenby. During production of the 1969 James Bond movie "On Her Majesty's Secret Service", O'Rahilly talked Lazenby into refusing a seven-movie Bond contract on grounds that the James Bond character was out of touch with the times, and would not successfully continue into the 1970s.

In the 1970s O'Rahilly, noticing that people "found it easier to talk about hate than love", developed the philosophy of "Loving Awareness", which has been heavily promoted on Caroline ever since. In 1976 an album of songs based on the concept was recorded by the Loving Awareness Band, a group assembled by O'Rahilly for the purpose.

On Monday 3rd Dec 2007, Ronan was inducted as a Fellow of the Radio Academy .

O'Rahilly's parents owned the port of Greenore in Carlingford Lough County Louth, and his grandfather Michael Joseph O'Rahilly was notably killed in the Easter 1916 Irish Nationalist rebellion in Dublin.