A quasiclassical trajectory analysis of the reaction of O(P-3) with HCl at a collision energy of 3.2 kcal/mol is presented. The potential surface used is based on ab initio calculations at the MRCI level. The MRCI energies with the Davidson correction (MRCI + Q) were scaled in a manner similar to the scaling external correlation (SEC) method of Brown and Truhlar and fitted to a simple analytic function. This surface has a reaction barrier of approximately 10.06 kcal/mol. The classical dynamics of the reaction are studied by initiating 20000 trajectories in each of the three initial states HCl (v = 2, j = 1, 6, 9). The results are compared to the experiments of Zare and coworkers.