Photographic evidence is presented of the back‐face spallation of 1.0‐mm 6061‐T6 aluminum samples irradiated in vacuum by 1.5‐nsec 1.06‐&mgr; laser pulses. Thinner samples (0.5 mm) have also been spalled and complete back‐face separation has been achieved. It is demonstrated that the degree of spallation is a strong function of fluence and that target coupling can be enhanced by means of prepulses.