Advanced Organic Chemistry: Part A: Structure and Mechanisms by Francis A. Carey and Richard J. Sundberg is a foundational textbook for advanced undergraduates and graduate students, focusing on the fundamental principles of chemical bonding, molecular structure, stereochemistry, and reaction mechanisms like nucleophilic substitution, aromatic substitution, and free radical reactions. It serves as a comprehensive guide, often paired with Part B (Reaction and Synthesis), to provide a deep understanding of organic chemistry's core concepts and patterns of reactivity.