It is generally supposed that diffusion is the main factor controlling the process of powder sintering. In this work it is shown that plastic deformation achieved by means of dislocation movement is also an important constituent of the sintering process. Since temperature essentially affects dislocation mobility, the temperature ranges of cold, warm and hot deformation are discussed. The stresses occurring on powder sintering leading to plastic deformation of the material are estimated. On the base of results recommendations are made for selecting the optimal condition for the sintering of powders.