The present analysis of the origin and evolution of the solar system represents a fusion of two initially independent approaches to the problem. One of us (Alfven) started from a study of the physical processes (1942, 1943a, 1946; summarized in a monograph in 1954), and the other (Arrhenius) from experimental studies of plasma-solid reactions and from chemical and mineralogical analyses of meteorites and lunar and terrestrial samples. Joined by the common belief that the complicated events leading to the present structure of the solar system can be understood only by an integrated chemical-physical approach, we have established a collaboration at the University of California, San Diego (UCSD), in La Jolla, during the last seven years. Our work, together with that of many colleagues in La Jolla, Stockholm, and elsewhere, has resulted in a series of papers describing the general principles of our joint approach, experimental results, and model approximations for some of the most important processes. The present volume is a summary of our results, which we have tried to present in such a form as to make the physics understandable to chemists and the chemistry understandable to physicists. Our primary concern has been to establish general constraints on applicable models. Hence we have avoided complex mathematical treatment in cases where approximations are sufficient to clarify the general character of the processes.