At an early stage of his career he was one of the Australian Ballet's rehearsal class pianists, and later performed live music for ballet performances such as Signatures, An Evening, Seven Deadly Sins and Nearly Beloved.
[2] Ross Edwards dedicated his Piano Concerto (1982) to Hennig,[3] who was soloist at the premiere performance in 1983 with the Queensland Symphony Orchestra under Werner Andreas Albert.
[6] He played the piano for the music for Jane Campion's first film Two Friends.
[7] Dennis Hennig died of an AIDS-related condition[8] in early 1993, aged 41.
A medal in his memory is presented at the Sydney International Piano Competition.