This study guide for the Chemistry Olympiad contains summarized concepts and examples in all areas of chemistry. The chapters are arranged in a logical manner and establishes connections between concepts. Undergraduate chemistry concepts are explained clearly: every equation in physical chemistry is derived and justified while every organic reaction has its reaction mechanism shown and explained, without assuming that readers have university-level background in the subject. The book also contains original Chemistry Olympiad sample problems that readers may use to test their knowledge. This is a first book of its kind, written by Nan Zhihan, International Chemistry Olympiad (IChO) gold medallist and winner of the International Union of Pure and Applied Chemistry (IUPAC) Prize for achieving the highest score in the experimental exam, and experienced Chemistry Olympiad trainer Dr Zhang Sheng, who has served as head mentor of Singapore IChO team for many years. It builds on the experience of both a participant and trainer to help any aspiring Chemistry Olympiad student understand the challenging concepts in chemistry.