Plasma nitriding of MC2, a single crystalline (gamma/gamma') Ni-based superalloy, was performed at 400 degrees C for 1 and 4 h. Owing to its monomodal gamma' particle size distribution, MC2 was used as a model material in an attempt to investigate the behavior of precipitates during the nitriding of a gamma matrix. The nitrogen profiles, the morphology, and the nature of the phases in the nitrided layer were characterized by glow discharge optical emission spectroscopy, scanning electron microscopy, and X-ray diffraction. The c matrix appeared to be nitrided similarly to the gamma solid solution in austenitic stainless steels with the development of an expanded gamma(N) phase. The amount of nitrogen in the gamma matrix varies from similar to 30 at.% at the surface till similar to 20 at.% at the interface with the non nitrided matrix. On the contrary, the gamma' precipitates accommodate no more than few at.% of nitrogen. This disparity modifies the morphology and the average gamma channel width increased by similar to 25 %.