It was the aim of the 10th workshop in Gwatt (Switzerland), October 1986 to elucidate the twofold impact of physics on the life sciences. On the one hand, the powerful techniques developed for studying complex physical phenomena are very useful in the biological context. Equally useful, on the other hand, are certain physical concepts, such as symmetry and symmetry breaking, linear and nonlinear stability, frustration and constrained dynamics. In this respect the book presents exemplary contributions on topics such as - studies of the symmetries and structure of biological systems using NMR, electron microscopy and image processing; - thermodynamics and transport properties of biomembranes; - physics of proteins and applications in biotechnology; - neural networks and brain research; - the theory of evolution. Researchers in physics, particularly in statistical and biophysics, biology, physiology and medicine will find this book an excellent survey of the most lively fields of physics in living matter.