Each chapter contains strategically positioned sections that cover important skills. In each section, an important skill is developed or fine-tuned. Multiple problems are then provided in order to build competence in that skill. Students are given the opportunity to master each core skill before moving on to the next section. The end-of-chapter exercises integrate the skills developed throughout the chapter. Three short chapters (Chapters 7, 12, and 24) are devoted entirely to skill development (proposing mechanisms and proposing syntheses).