Abstract We discuss the control of the kinetics and dynamics of chemical reactions by the solvent, from a molecular point of view. The kinetics are discussed using a transition state theory (TST) approach, applied to the reactants and their surrounding solvent as one supramolecule. The topics discussed include a molecular interpretation for the changes that take place when one solvent is being replaced by another; the use of local against normal vibrational modes and/or joint description, i.e., local modes for part of the system and normal modes for the other part; and the effect of pressure on the rate in solution. The notion of free volume and volume of activation is extended to a more general phase space in which geometrical volumes may overlap, the approximations that are inherent to cell theory are examined and a molecular interpretation for internal and chemical pressures is suggested. The link to the dynamics is provided by an analysis of the breakdown of TST due to diffusion/cage control of the ra...