Book excerpt: "Introduction to Theoretical Organic Chemistry" provides an introduction for chemists with a limited mathematical background, yet need a working understanding of quantum chemistry as applied to problems in organic chemistry. This book is unique in that it is written at the level of the advanced undergraduate or beginning graduate student in organic chemistry, whose exposure to theoretical chemistry is relatively recent. It fills a niche in that most books on theoretical organic chemistry are written by theoretical or computational chemists, whereas this book is written by an organic chemist. The book covers molecular modeling computer software, and offers a useful guide to the scope and limitations of each program, along with specific examples of input and output for several of the most popular software. Numerous examples and exercises are provided.