[en] Phosphorus-doped oxygen-free copper will be used as the outer barrier in canisters that will contain spent nuclear fuel in the proposed Swedish underground repository. The possibility of stress corrosion cracking (SCC) is a concern, in view of isolated reports of cracking or intergranular corrosion of pure copper in sulfide solutions. This concern was addressed in the present work using copper tensile specimens provided by SKB. Methods included slow strain rate testing, constant strain tensile testing, electrochemical and surface analytical studies of corrosion products, and electron backscatter diffraction analysis of grain orientation effects on corrosion. The base solutions were prepared from NaCl or synthetic sea water with addition of varying amounts of sodium sulfide at room temperature and 80 degree Celsius. No SCC was found in any of the testing, for a range of sulfide concentrations from 5-50 mM at room temperature or 8 C, including tests where small anodic or cathodic potential displacements were applied from the open-circuit (corrosion) potential. Neither was SCC found in constant-strain immersion testing with very large strain. The Cu2S corrosion product is generally very coarse, fragile, and easily spalled off in severe corrosion environments, i.e. high sulfide concentration, high temperature, less perfect de aeration, etc. But it could also consist of very fine grains, relatively compact and adherent, on particular grain orientations when it was formed on an electro polished surface in a very well-deaerated solution. These orientations have not yet been identified statistically, although some preference for thin, adherent films was noted on orientations close to (100). The notion that the corrosion reaction is always controlled by inward aqueous-phase diffusion of sulfide may thus not be unconditionally correct for this range of sulfide concentrations; however it is hard to distinguish the role of diffusion within pores in the film. In the actual repository, the limiting flux of sulfide to the canister surface will be some orders of magnitude lower, in view of the bentonite barrier which imposes a lower diffusivity and much longer diffusion length. Preferential corrosion along grain boundaries was rarely observed, which is considered to be important for SCC resistance since there was usually a fairly rapid general corrosion, at least on one side of the grain boundary. Severe plastic deformation was not found to cause any particular localization of corrosion, but may promote general corrosion in the deformed area. On the basis of this work, SCC of copper in sulfide solution, obtained by Japanese workers using slow strain rate testing of copper sheet, appears not to be reproducible in the SKB copper using normal tensile specimens. Neither can we rationalize, on the basis of our results, the findings of Finnish workers on intergranular corrosion emanating from a fatigue crack tip. Some complexities related to these other studies are discussed, including the possible effect of poor de aeration or inappropriate potential control; however a discrepancy remains nonetheless