As a member of "Tango Five", a group founded in 1985, he performed at the World Exhibitions in Sevilla 1992 and Hannover 2000, the Olympic Games in Athens 2004,as well as Tango Festivals in Montevideo and Buenos Aires in 1998.From 1995 - 1999 he was a member of "Philharmonia Virtuosi", the Chamber Orchestra of the Metropolitan Museum.
In the last years Gregor Huebner has appeared on Jazz festivals in Kork (Ireland), Tiblisi (Georgia), Montreux, New York (JVC, Bell Atlantic),Hollywood Bowl LA (Tango Festival) Stuttgart (Jazz Open) and Porto (Portugal). He performed at Carnegie Hall, the Apollo Theater, the Berlin Philharmonie. Frauenkirche in Dresden, Gewandhaus Leipzig and traveled to Southeast Asia, Japan, Russia, Columbia, Mexico, Hawaii, Georgia and Spain.