The scattering of spin polarized neutron beams is the most sensitive experimental technique for studying the distribution and dynamics of the magnetism in solids at the atomic level. Several new methods have emerged during the past 10-15 years, and polarized neutrons are now also being used, for example, to investigate nuclear magnetism, surface magnetism and, through neutron spin echo spectroscopy, diffusive and spin relaxation processes over time scales of 10-9 - 10-12 seconds. This book provides the experimental condensed matter researcher with a description of the variety of material characteristics which can be investigated with polarized neutrons. There are two extensive chapters on basic theory and currently available instrumentation, and this is followed by a presentation and discussion of scientific results obtained from a wide range of experiments: diffraction, critical reflection, elastic and inelastic polarization analysis, and neutron spin precession methods like spin echo spectroscopy.