Chapter 1. Heuristics and organic synthesis. Pure Substances. Chapter 2. The reactivity of organic molecules. Chapter 3. Methodologies. Chapter 4. Synthetic structural analysis. Simplification. Heterolytic disconnections: Heuristic principles. Chapter 5. Synthesis of dissonant systems. Chapter 6. Cyclic and polycyclic systems. Chapter 7. Systems with unusual structural features: Quaternary carbon atoms, medium-sized rings and bridged systems. Chapter 8. Stereochemical control in cyclic and polycyclic systems. Chapter 9. Acyclic diastereoselection. Chapter 10. Organic synthesis. Concluding remarks. Chapter 11. Computer-assisted organic synthesis. Chapter 12. Selected organic syntheses. Appendix 1. Graph theory. Molecular complexity indices. Appendix 2. CHAOS: Instruction manual. Appendix 3. CHAOS: Disconnection Groups. Appendix 4. Suggested exercises to be solved by CHAOS. Subject index.