We report quantum wave packet calculations on the H' + HBr (v = 0, j = 0) -> H-2 (v', j') + Br reaction over collision energies in the range 2.1-2.5 eV. The product rotational distributions show good agreement with previous experimental results and quasi-classical trajectory predictions. We report the first quantum differential cross sections for this system, which show strong forward scattering into rotationally excited products. Cuts through the wave packet show evidence of an additional rapid reaction mechanism, in which the system first visits the H'Br + H exchange arrangement. (c) 2007 Elsevier B.V. All rights reserved.