When painting a wall, better coverage is assured when the roller passes over the same area several times from different directions. It is the opinion of the author that this technique works well in teaching chemistry. Therefore, a second objective has been to stress fundamental principles in the discussion of several topics. For example, the hard-soft interaction principle is employed in discussion of acid-base chemistry, stability of complexes, solubility, and predicting reaction products. Third, the presentation of topics is made with an effort to be clear and concise so that the book is portable and user friendly. This book is meant to present in convenient form a readable account of the essentials of inorganic chemistry that can serve as both as a textbook for a one semester course upper level course and as a guide for self study. It is a textbook not a review of the literature or a research monograph. There are few references to the original literature, but many of the advanced books and monographs are cited. Although the material contained in this book is arranged in a progressive way, there is fl exibility in the order of presentation. For students who have a good grasp of the basic principles of quantum mechanics and atomic structure, Chapters 1 and 2 can be given a cursory reading but not included in the required course material. The chapters are included to provide a resource for review and self study. Chapter 4 presents an overview structural chemistry early so the reader can become familiar with many types of inorganic structures before taking up the study of symmetry or chemistry of specifi c elements. Structures of inorganic solids are discussed in Chapter 7, but that material could easily be studied before Chapters 5 or 6. Chapter 6 contains material dealing with intermolecular forces and polarity of molecules because of the importance of these topics when interpreting properties of substances and their chemical behavior. In view of the importance of the topic, especially in industrial chemistry, this book includes material on rate processes involving inorganic compounds in the solid state (Chapter 8) . The chapter begins with an overview of some of the important aspects of reactions in solids before considering phase transitions and reactions of solid coordination compounds. It should be an acknowledged fact that no single volume can present the descriptive chemistry of all the elements. Some of the volumes that attempt to do so are enormous. In this book, the presentation of descriptive chemistry of the elements is kept brief with the emphasis placed on types of reactions and structures that summarize the behavior of many compounds. The attempt is to present an overview of descriptive chemistry that will show the important classes of compounds and their reactions without becoming laborious in its detail. Many schools offer a descriptive inorganic chemistry course at an intermediate level that covers a great deal of the chemistry of the elements. Part of the rationale for offering such a course is that the upper level course typically concentrates more heavily on principles of inorganic chemistry. Recognizing that an increasing fraction of the students in the upper level inorganic chemistry course will have already had a course that deals primarily with descriptive chemistry, this book is devoted to a presentation of the principles of inorganic chemistry while giving an a brief overview of descriptive chemistry in Chapters 12–15, although many topics that are primarily descriptive in nature are included in other sections. Chapter 16 provides a survey of the chemistry of coordination compounds and that is followed by Chapters 17–22 that deal with structures, bonding, spectra, and reactions of coordination compounds. The material included in this text should provide the basis for the successful study of a variety of special topics.