The kinetics of sintering of Co-Fe materials was studied. The main objective of the work was to establish the effects of iron content and sintering parameters on the microstructure and phase composition of the as-sintered materials. Specimens containing from 3 to 25 wt.% iron were sintered in a dilatometer for one hour at 900, 1000 and 1150OC in either hydrogen or nitrogen atmosphere. The length of specimens during the heating, hold at the temperature and cooling steps were monitored to establish the sample’s shrinkage. Microstructural observations were carried out on polished and etched transverse sections which were also subjected to the X-ray phase analysis.