After an abortive contract with Polydor, which yielded one unsuccessful single, the pair joined Apple Corps as staff songwriters and wrote several songs for Mary Hopkin.

This band made two well-received albums and scored two Top 5 singles in Britain with "When I'm Dead and Gone" and "Malt and Barley Blues", before Gallagher and Lyle left to work as a duo.

This set spawned two British Top 10 singles, "I Wanna Stay With You" and "Heart on My Sleeve",[7] both of which also charted in the US; the latter song was covered successfully by Bryan Ferry.

[6] The duo's next album, Love on the Airwaves, likewise produced by Kershenbaum, went silver in the UK but yielded only one minor hit single, "Every Little Teardrop" which peaked at #32.

A song recorded for this set, "A Heart in New York", was covered by Art Garfunkel for his album Scissors Cut and became a major US Adult Contemporary hit for him in 1981.

[11] After a spell with Dr Hook as bassist during 1999 and 2000,[12][13] Gallagher embarked on a solo career as a singer-songwriter, touring the folk club and festival circuits.

[14] The pair subsequently re-formed and performed at two events in 2011: "The Big Gig" at Glasgow's Barrowland nightclub, alongside Marti Pellow, Jim Diamond and Midge Ure,[15] and the MOARE Festival in Faversham, Kent, which was headlined by former Average White Band stalwart Hamish Stuart.

[20] The summer of 2017 saw the duo perform as part of the 'Byre at The Botanics' season in St Andrews,[21] and also at the Belladrum Festival in Inverness[22] and the Albany Theatre in Greenock.

[29] Gallagher was made a Companion of LIPA (Liverpool Institute for Performing Arts) by Paul McCartney in 2001 in recognition of his work as a songwriting coach at the college.