He met Dave Holland, Kenny Wheeler, Steve Coleman, John Abercrombie, Richie Beirach and David Liebman at the Banff Centre in Alberta, Canada in 1985 and 1986.

He founded his long-running quartet featuring at various times guitarist Ben Monder, drummers John Hollenbeck, Owen Howard, bassists Scott Colley and Peter Herbert, and pianists Henry Hey, Andy Ezrin, and David Berkman.

His second, Terra Infirma was released in 1995 by EMI France, produced by David Liebman, and featuring the quartet of Middleton, pianist Renee Rosnes, bassist Paul Imm, and drummer Alan Jones augmented by a horn section.

The Fensters was a two saxophone, bass and drums formation featuring Middleton, Alan Jones, the saxophonist and composer François Theberge, and bassist Paul Imm.

"Nomad's Notebook" was followed by his 2nd production for the German label Intuition Music and Media featuring trumpeter Kenny Wheeler and trombonist Nils Wogram entitled "Reinventing the World".