Leaving teaching in 1997 to pursue his career as a composer, he wrote his first film score in 2002 for The Incredible Mrs Ritchie, directed by Paul Johansson.

From 2006 to 2007 Hawes was Composer in Residence at Classic FM where he was commissioned to write twelve pieces for piano, with each premiered over a twelve-month period.

Hawes joined forces with Thomas once again, and also with Julian Lloyd Webber, for his subsequent album Fair Albion: Visions of England.

[6] Hawes' Lazarus Requiem premiered at the Cadogan Hall, London in 2008 and the work was recorded in January 2012 by the Royal Scottish National Orchestra, Exeter Philharmonic Choir, Exeter Cathedral Choir and the soloists Thomas Walker, Elin Manahan Thomas, Rachael Lloyd, and Julian Rippon.

The work intersperses the traditional Latin Requiem text with an account in English of the raising of Lazarus from St John's Gospel.

[8] Recorded with soprano Grace Davidson, the Choir of New College, Oxford and the Royal Philharmonic Orchestra the album depicts angels in their many forms.

As part of the commemorations of remembrance to mark the First World War, Hawes was commissioned by the Sheringham & Cromer Choral Society in Norfolk to write a large-scale work for choir and orchestra based on the life of nurse Edith Cavell, a heroine of the war who saved many hundreds of soldiers at great risk to herself.

Hawes was commissioned to write a work for the Aliquando Choir of Henley-upon-Thames based on the words of the Wilfred Owen poem I know the Music for their commemoration of the First World War in November 2014.

His eighth album, Revelation, released on Naxos Records February 2017, saw Hawes collaborate with Grammy and Juno-nominated Elora Singers, Canada.