The annealing behaviour of Ti(C 0.5 N 0.05 )–40wt.% W and Ti(C 0.5 N 0.5 ) 0.6 –40wt.% W mechanically alloyed powders was investigated using XRD, TEM, SEM and DTA techniques. It was observed that the reaction start and finish temperatures between constituents were lower in the system that had higher residual lattice strains after milling. The compositions of the intermetallic compounds and solution phases formed were dependent of the milling conditions and the annealing temperature. Thermal alloying was observed during annealing of Ti(C 0.5 N 0.05 )–40wt.% W mechanically alloyed products, whereas de-mixing of W-rich phases from the metastable solid solution occurred during annealing of the Ti(C 0.5 N 0.5 ) 0.6 –40wt.% W milled powders.