[en] Secondary ion mass analysis (SIMS) is used to investigate the effect of laser annealing on the distribution of boron in the surface region of (100) silicon. Pulsed laser annealing was carried out using the Q-switched output of a ruby laser (20 x 10^-9 sec pulse duration time). Above a pulse threshold energy of approx. 1/J cm^-2, substantial alteration of the as-implanted profile of B occurred. The as-implanted profile was very nearly Gaussian, but after annealing the profile was almost uniform from the surface down to a depth of approximately twice the projected range. Redistribution of B was found to be both pulse energy and pulse number dependent. The effect of laser annealing on a thin evaporation deposited layer of B on (100) silicon was also studied. In this case a monotomically decreasing profile which resembled a Gaussian peaked at the surface resulted. A possible explanation for the redistribution of B in the surface region of (100) silicon involves melting of the near surface region during laser irradiation