Cecil called him "a very hard worker" and a "Group One Jockey" while Richard Edmondson, writing in The Independent, praised Fallon's riding ability while pointing out his poor disciplinary record.

In 1999 he won his first Derby when he rode the Cecil-trained Oath to victory at Epsom and followed up by winning the Oaks on Ramruma for the same stable.

During his time with Stoute, Fallon rode the winners of many important races including successive runnings of the 2000 Guineas with King's Best and Golan.

Between these two victories, Fallon lost his Champion Jockey title after a serious arm injury sustained in a fall in June 2000 at Royal Ascot[4] forced him to miss several months race-riding.

On 7 December 2007, the judge decided the defendants had no case to answer and he directed the jury to find Fallon and all his co-defendants not guilty because of lack of evidence.

Fallon's 2006 ban from riding in England curtailed his opportunities, but more important wins followed for the Ballydoyle team, notably on the 2007 European Horse of the Year Dylan Thomas.

Fallon's position with O'Brien ended with his 18-month worldwide ban imposed by the French racing authorities in January 2008.

On 29 November 2006 French racing authority France Galop suspended Fallon for six months after testing positive for a metabolite of a prohibited substance after riding at Chantilly on 9 July 2006.

[11] The 2010 Flat racing season saw Kieren Fallon employed largely by trainers Luca Cumani, Mark Johnston and Kevin Ryan.