Stress intensity factors are presented for a hollow circumferentially notched round bar subjected to tension, torsion, bending, and transverse shear. These previously undetermined factors are calculated from the limiting values of stress concentration factors for a small notch root radius. The stress intensity factors obtained are compared with results obtained by other investigators, when possible, and a favorable correlation is observed. The accuracy is further indicated by the good agreement of the fracture toughness of 7075-T6 aluminum, determined in a series of tension and bending tests conducted on hollow notched round bars, with the corresponding value obtained by other investigators.