Wentworth has a long association with Pink Floyd founding member Roger Waters, and co-produced, orchestrated and conducted the music for his opera, Ça Ira.
In August of the same year he conducted Ça Ira which opened the annual Cultural Festival at the Gotaplatsen in Gothenburg and featured an international cast of singers, Sally Matthews, Bryan Hymel, Owen Gradus and Christian Van Horn including Roger Waters who acted as narrator to an audience of over ten thousand.
Wentworth also orchestrated and conducted the modern opera Giulietta e Romeo in 2007 for European composer Riccardo Cocciante, which had its premiere at the Arena in Verona and has subsequently toured throughout Italy.
Other collaborations include writing and producing songs with George Benson, Patti Austin, Grace Jones and Paul McCartney, who commissioned him to orchestrate and conduct a personal animated film entitled The Light From Within (yet to be released).
He also collaborated with writer David Levin and wrote six songs for his 2009 musical production People, which premiered at the Edinburgh Festival in that year.