A self-taught musician, Mooney was influenced by the blues from an early age and his hard-bop style of guitar playing is expressive and melodic with a bluesy groove. He possesses a warm and rich tenor voice and has an almost flawless sense of pitch.

His first album, "All My Love's In Vain" (Rubyworks) was released in 2005 to critical acclaim and has become one of Ireland's highest selling albums by a jazz artist. The single, "Beautiful Day" charted on the Irish hit parade and still receives regular airplay.

Nigel Mooney's primary influences had been the "Kings" of Chicago; by the early nineties his guitar playing was being coloured by the influence of guitarists such as Grant Green, Wes Montgomery and George Benson, and other instrumentalists such as Charlie Parker, Stanley Turrentine, Erroll Garner and Ahmad Jamal. In the early nineties he met and befriended Georgie Fame, a kindred spirit whose musical influences were similar to Mooney's; both singers have guested with one another on many occasions since.