The reaction force F(R) and the reaction force constant κ(R) provide a rigorously based approach to characterizing a chemical process. The energies associated with its different stages are presented and discussed for a number of examples. Analysis of these suggests an alternative, modified expression for the Hammond-Leffler postulate. We show that diabatic analysis leads to a description of the process that is qualitatively very similar to that coming from F(R) and κ(R), quantitatively so for proton-transfer reactions. Reaction force analysis provides a unifying framework that can encompass a variety of independent concepts relating to chemical processes.