A part of the Ti-W-C-N system has been investigated by heat treating alloys at 1750C. The equlibria involving the (Ti, W) C-phase is 22 at % (atomic per cent) in the three-phase equilibrium with graphite and WC at 1750C. The partitioning of tungsten and titanium between the (Ti,W) C-phase and bcc (body centered cubic, A2)-(Ti, W) is in close agreement with published phase diagrams. By alloying witj nitrogen the cubic gamma phase decomposes into a titanium nitride and a tungsten-rich carbide phase.