A set of stereochemical rules based on the CIP configurational descriptors have been proposed for the specification of the stereochemical outcome of asymmetric transformations. This simple and unambiguous system denotes the steric approach involving prochiral faces and stereogenic centers of reactants, either in enantio- or diastereoselective synthesis. The descriptors form chiral codes of symbols and numbers, which are susceptible of computerization. A brief discussion and comparison with other terms currently employed in dynamic stereochemistry are also given. Copyright (C) 1996 Elsevier Science Ltd