John Cooney was born in Manchester. After reading Music at Cardiff University he studied composition at the Royal College of Music and the Guildhall School of Music and Drama, where his teachers included Simon Bainbridge, George Benjamin, Robert Saxton and Anthony Powers. He also attended courses led by Colin Matthews, Oliver Knussen, Per Nørgård and Peter Eötvös.
A first encounter with the music of Magnus Lindberg in 1991 made a big impact and led to private study with Lindberg in London and Paris. In addition to the continuing importance of Lindberg's music, more recent influences include the music of Pascal Dusapin and Unsuk Chin. Cooney's music also draws inspiration from poetry and visual art, particularly the poems of Philippe Jaccottet and the paintings of Per Kirkeby and Jon Schueler.
Cooney's music first drew critical attention when, as a student, he was awarded the Royal Philharmonic Society Composition Prize. Other prizes followed, including the Arts Council Dio Fund Award and the Japan International League of Artists Chamber Music Prize. Cooney has been Composer in Association with the Allegri String Quartet and was Composer in Residence with the Scottish Chamber Orchestra on both the Ninth and Tenth Strathclyde Concerto Projects.
Cooney's music has been commissioned and performed by a wide array of ensembles including the Nash Ensemble, Allegri String Quartet, London Sinfonietta, Scottish Chamber Orchestra, Delta Saxophone Quartet, Chroma, Psappha, Capricorn and Brunel Ensemble. His music has also been included in the Aldeburgh, Huddersfield, Spitalfields, Bath and Vale of Glamorgan festivals.
John Cooney is renowned for his work in music education and currently teaches composition at the Yehudi Menuhin School and the Royal Academy of Music Junior Department. In recent years he has been increasingly sought after as a lecturer, holding posts as a Visiting Lecturer in Composition at Royal Holloway, University of London and Associate Tutor in Composition at Cardiff University. In addition he has led major education projects for the BBC Scottish Symphony Orchestra, English National Opera, South Bank Centre, Brodsky Quartet, City of London Sinfonia, London Sinfonietta, Huddersfield Contemporary Music Festival and many others. Projects abroad include the ISCM World Music Days in Yokohama, Ile de France Opera et Ballet and Muziekcentrum Vredenburg.