1 Introduction.- 1.1 Passivity, Optimality, and Stability.- 1.2 Feedback Passivation.- 1.3 Cascade Designs.- 1.4 Lyapunov Constructions.- 1.5 Recursive Designs.- 1.6 Book Style and Notation.- 2 Passivity Concepts as Design Tools.- 2.1 Dissipativity and Passivity.- 2.2 Interconnections of Passive Systems.- 2.3 Lyapunov Stability and Passivity.- 2.4 Feedback Passivity.- 2.5 Summary.- 2.6 Notes and References.- 3 Stability Margins and Optimality.- 3.1 Stability Margins for Linear Systems.- 3.2 Input Uncertainties.- 3.3 Optimality, Stability, and Passivity.- 3.4 Stability Margins of Optimal Systems.- 3.5 Inverse Optimal Design.- 3.6 Summary.- 3.7 Notes and References.- 4 Cascade Designs.- 4.1 Cascade Systems.- 4.2 Partial-State Feedback Designs.- 4.3 Feedback Passivation of Cascades.- 4.4 Designs for the TORA System.- 4.5 Output Peaking: an Obstacle to Global Stabilization.- 4.6 Summary.- 4.7 Notes and References.- 5 Construction of Lyapunov functions.- 5.1 Composite Lyapunov functions for cascade systems.- 5.2 Lyapunov Construction with a Cross-Term.- 5.3 Relaxed Constructions.- 5.4 Stabilization of Augmented Cascades.- 5.5 Lyapunov functions for adaptive control.- 5.6 Summary.- 5.7 Notes and references.- 6 Recursive designs.- 6.1 Backstepping.- 6.2 Forwarding.- 6.3 Interlaced Systems.- 6.4 Summary and Perspectives.- 6.5 Notes and References.- A Basic geometric concepts.- A.1 Relative Degree.- A.2 Normal Form.- A.3 The Zero Dynamics.- A.4 Right-Invertibility.- A.5 Geometric properties.- B Proofs of Theorems 3.18 and 4.35.- B.1 Proof of Theorem 3.18.- B.2 Proof of Theorem 4.35.