These Proceedings contain invited lectures presented at the third Interna tional Conference on "Irreversible Processes and Dissipative Structures" in Kiihlungsborn (German Democratic Republic) in March, 1985. These con ferences, the first of which was held in Rostock in 1977 and the second in Berlin in 1982, are devoted to the study of irreversible processes far from thermal equilibrium and to the phenomena of selforganization. The meet ing in Kiihlungsborn brought together some 160 mathematicians, physicists, chemists and biologists from 10 countries, who are all interested in the inter disciplinary field of synergetics. The main topics of the conference were basic concepts of selforganization and evolution, such as entropy, instabilities, nucleation, dissipative struc tures, chaos and turbulence. The contributions cover methods from ther modynamics, the theory of dynamic systems, stochastic and statistic theory, the method of Green's functions, the fluctuation-dissipation theorem, etc. Several problems are studied in more detail, e.g., the kinetics of nucleation especially in finite systems, the dynamics of interfaces, reaction-diffusion sys tems, chemical and biochemical pattern formation and information process ing. Further, several contributions are devoted to the development of the concepts of chaos and turbulence. The editors hope that the contributions collected in this volume will pro vide some new information about the field of selforganization, which is in full development now.