The initiation and propagation of microfractures and their contribution to material failure in compression are examined. The early part of the fracture process, the lateral and the axial yield points of the stress-strain curves, are identified with the onset of microfracture, respectively at the tensile and the compressive stress concentrations of the elastic flaw boundary. Later stages, including the initiation of inclined shear fractures, the mobilization of total resistance and the reduction of strength to the residual level, are discussed in terms of a modified Coulomb model.