Father of twin daughters Charlotte and Chloe Dean Gaffney who lives with his partner Sarah in Cobham, trained at the Sylvia Young Theatre School in Marylebone, London. He is best known for playing the role of Robbie Jackson in the popular BBC soap opera, EastEnders. Gaffney joined the show in 1993 and remained in the role for ten years.

In 2003 Gaffney took part in the ITV reality television series The Club. Gaffney took on management of a bar in a London club named Nylon and competed with two other celebrities, Richard Blackwood and Samantha Fox, to be awarded the title of 'the most successful bar manager'. Gaffney was the eventual winner.

On September 12th 2006 it was announced that Gaffney, Linda Robson and ex-EastEnder Nicola Stapleton are all to guest-star on the long-running ITV serial drama The Bill. Gaffney will play Gavin Josef, a cocky wide-boy who is connected to an assault investigation. All three artists have filmed their parts and are scheduled to be on-screen in November.

Gaffney then provided TV viewers with what was probably one of the funniest ever reality TV moments  appearing on the 2006 series of the ITV reality show, I'm a Celebrity, Get Me out of Here!. However, he has received more praise and fantastic reviews for his comical role in Ricky Gervais’s “Extra’s” Christmas special.

Gaffney is an avid supporter of Brentford F.C.