The statistical theory of sintering is modified to account for the new concept of pore coordination number (after Lange) as well as other refinements of the original assumptions (after Kuczynski). A general morphological kinetic equation is developed for uniform microstructures with pores located at the grain boundaries. This equation provides for contributions of grain boundary and volume diffusion to densification and is unrestricted with respect to the type of firing schedule imposed. Using this modified model, one may evaluate the significant parameter x, a measure of 'the path of microstructural evolution'.