Although I have never been actively engaged in research on thermodynam ics, per se, I have had to utilize it while attempting to develop theories better able to deal with various kinds of nonlinear macroscopic phenom ena encountered in materials. In trying to help younger workers to start in research of this kind, I have been impressed with how little most of them know about common and elmentary applications of thermodynamics to solids, although they have taken at least one elementary course in thermo dynamics at some university. Observation of a number of elementary books on thermodynamics indicates that this is due more to lack of exposure to such ideas than to some fault of the students. When my department had a service course become obsolete, I accepted responsibility for developing a replacement course dealing with such appli cations. The intended audience consisted of seniors and beginning graduate students from various engineering and scientific departments. To make the course accessible to the various groups meant keeping the prerequisites to a minimum, so I settled on mastery of calculus as the basic requirement. The first nine chapters of this book represent lecture notes developed for this purpose. In the actual lectures some constituents of the tenth chap ter are mentioned, but this has not been an integral part of the course.