The basic relations which govern the behavior of titanium alloys in the presence of stress concentrations, as caused by notching, were investigated for cylindrical and prismatic tension test specimens. Notch tensile strengths were determined, at room temperature, for 4340 steel heat-treated to various strength levels, and for the titanium alloys 6Al-4V and 5Al-1.5Fe-1.4Cr-1.2Mo (Ti-155A). Some effects of notch geometry, specimen shape, type of loading, material history, and test temperature were included in the investigation. The information acquired from these studies leads to recommendations pertaining to the design of notch tensile specimens for evaluating the relative notch sensitivity of titanium sheet alloys.