The book Classical Thermodynamics of Fluid Systems: Principles and Applications written by professor Juan H. Vera and Dr. Grazyna Wilczek-Vera is undoubtably a book written in a most personal style by the two distinguished authors.The book contains four sections and a fifth one with appendices (mostly on selected thermodynamicmodels). The first two sections contain a total of 18 chapters on fundamentals of thermodynamics andmixtures, including phase diagrams. These chapters on the fundamentals are presented in a very rigorous, mathematicaland rather condensed way, in carefully formulated short chapters, with a minimum number of figures, tables, examples and references. The terminology and nomenclature is clear and consistent across the whole book.The interrelations between the thermodynamic properties and variables are presented in an exceptionally clearway and an excellent illustration of this is the equation on the cover page of Section II. Especially Chapters14 and 15 present these interrelations of thermodynamic properties in a very comprehensive way. With the exception of Chapter 18 on electrolyte solutions, essentially no models which, as the authors say “come and go”, are presented in these first two sections. Electrolytes is an area of active research for many including theauthors of the book and it is, thus, not surprising that extra attention to electrolytes is given in various placesin the book, already in Section II. In addition to an entire chapter about electrolytes (Chapter 18), equilibriuminvolving ions is discussed in Chapter 10 and the use of molality as a measure of concentration in Chapter 15.