In December 2009, he and fellow academy coach Marc Bircham jointly assumed managerial duties for a match against West Bromwich Albion, after manager Jim Magilton was suspended; the game finished 2–2.
[citation needed] Gallen has two brothers, Joe and Kevin, both of whom played for QPR before also joining the coaching staff.
On 23 June 2016, Pegasus announced that Gallen would be the club's manager from the 2016–17 Hong Kong Premier League.
[6] Steve was appointed as Director of Football on 10 January 2020 soon after Charlton Athletic was taken over by East Street Investments.
On 9 September 2023, he took over as assistant manager of the Montserrat national football team under Lee Bowyer.