This 3rd edition has been expanded and updated to account for recent developments, while new illustrative examples as well as an enlarged reference list have also been added. It naturally retains the successful concept of its predecessors in presenting a unified perspective on molecular charge and energy transfer processes, thus bridging the regimes of coherent and dissipative dynamics, and establishing a connection between classic rate theories and modern treatments of ultrafast phenomena. Among the new topics are: - Time-dependent density functional theory - Heterogeneous electron transfer, e.g. between molecules and metal or semiconductor surfaces - Current flows through a single molecule. While serving as an introduction for graduate students and researchers, this is equally must-have reading for theoreticians and experimentalists, as well as an aid to interpreting experimental data and accessing the original literature.

On three occasions and at different locations, conferences were held to honor the eightieth birthday of Professor Herbert Frohlich: on the 18th December, 1985, in Liverpool, England; on the 14th February, 1986, in Stuttgart, Germany; and on the 8th March, 1986, on the Palm Coast, Florida. This Festschrift is a compilation of the papers of those conferences. Frohlich's choice of problems, from the earliest days, was couched in the phy sics of intrinsically interacting systems of excitation. One example, in which he set the course of research which is still followed, concerned dielectric breakdown, developed from the 1930's over several decades. The interacting systems are the electrons (receiving energy from an electric field) and lattice atom motion (taking energy from the electrons via "electron-phonon" interaction, hence heat dissipa tion). There is a threshold field above which the latter cannot keep up with the former, and the combined system (electrons plus phonons) "runs away"; that is to say, collectively it switches to a new state.