He began his career playing bass with Buddy Rich at the age of 18 and has continually been in demand as a session player over the years working with Noel Pointer, Ramsey Lewis, Ronnie Laws, Larry Carlton, Anita Baker, Galo Barbieri, Stephanie Mills, Jennifer Holiday, Red Rodney, George Benson and many more.

Gary has been involved in various aspects of production, arranging and conducting for the Celine Dion sessions. The first single "That's The Way It Is" from her Greatest Hits CD featured another Gary Haase song, "I Met An Angel", as its B-side. Celine decided to open with "I Met An Angel" on her 1999 television special. Like all of the Celine recordings, in each production Gary delves deep to produce the highest quality arranging, and mixing. It is this full blown, hands on approach that led Gary to N*Sync.

After writing the title track to N*Sync's Christmas CK, "Home For Christmas Day. This song not only appeared on the multi-million selling album but also was recorded as a duet with Rosie O Donnell.

Gary continues to work with and develop the new hit artists of tomorrow such as Heather Hedley (RCA), The Futures (Warner Music), or Northern Line (Global Talent). And ten year old sensation and Columbia