The first part of this three-volume treatment, Phonons: Theory and Exper­ iments I, has been devoted to the basic concepts of the physics of phonons and to a study of models of interatomic forces. The present second volume, Phonons: Theory and Experiments II, contains a thorough study of experimental techniques and the interpretation of experimental results. In a third volume we shall treat a number of phenomena which are directly related to lattice dynamics. The aim of this treatment is to bridge the gap between theory and ex­ periment. Both experimental aspects and theoretical concepts necessary for an interpretation of experimental data are discussed. An attempt has been made to present the descriptive as well as the analytical aspects of the top­ ics. Although emphasis is placed on the experimental and theoretical study of the dynamics of atoms in solids, most chapters also contain a general in­ troduction to the specific subject. The text is addressed to experimentalists and theoreticians working in the vast field of dynamical properties of solids. It will also prove useful to graduate students starting research in this or related fields. The choice of the topics treated was partly determined by the author's own activity in these areas. This is particularly the case for the chapters dealing with infrared, Raman and inelastic neutron spectroscopy, as well as for some newer developments such as the optical spectroscopy of thin films and adsorbates.