The 6th annual IEEE 3DUI contest focuses on Virtual Music Instruments (VMIs), and on 3D user interfaces for playing them. The Contest is part of the IEEE 2015 3DUI Symposium held in Arles, France. The contest is open to anyone interested in 3D User Interfaces (3DUIs), from researchers to students, enthusiasts, and professionals. The purpose of the contest is to stimulate innovative and creative solutions to challenging 3DUI problems. Due to the recent explosion of affordable and portable 3D devices, this year's contest will be judged live at 3DUI. The judgment will be done by selected 3DUI experts during on-site presentation during the conference. Therefore, contestants are required to bring their systems for live judging and for attendees to experience them.