Atomic Orbitals, Electron Spin, Linear Combinations.- Pauling ’3-Electron Bonds’, 4-Electron 3-Centre Bonding, and the Need for an ’Increased Valence’ Theory.- Wave-Functions and Valence-Bond Structures for 1-Electron Bonds, Electron-Pair Bonds, Pauling ’3-Electron Bonds’ and ’No Bonds’.- Valence-Bond Structures for Some Diatomic Molecules.- Pauling ’3-Electron Bonds’ and Hypoligated Transition Metal Complexes.- Pauling ’3-Electron Bonds’, 5-Electron 3-Centre Bonding and Some Tetra-Atomic Radicals.- Some Dimers of Triatomic Radicals with 17 and 19 Valence-Shell Electrons.- Some Cu(II) Binuclear Transition-Metal Complexes.- Excited States.- Pauling ’3-Electron Bonds’ and ’Increased Valence’ Theory for N2O4.- Pauling ’3-Electron Bonds’ and ’Increased-Valence’ Structures.- Increased-Valence Structures Constructed from Lewis Structures: Delocalization of Lone-Pair Electrons into Vacant Bonding Orbitals.- ’Increased-Valence’ Structures for N-Centre Bonding Units.- Delocalization of Lone-Pair Electrons into Antibonding Orbitals: Increased-Valence Structures, Molecular Orbital Theory and Atomic Valencies.- Slater Determinants and Wave-Functions for ’Increased-Valence’ Structures.- Classical Valence Structures and Quinquevalent Nitrogen Atoms.- Some Tetrahedral Molecules and dπ - Pπ Bonding for Some Sulphur Compounds.- Transition Metal Complexes with CO, N2, NO and O2 Ligands.- Some Electron-Excess σ Bonded Systems.- Intermolecular Donor-Acceptor Complexes.- Base-Displacement Reactions and Electron Conduction in Alkali Metals.- Free-Radical and Spin-Paired Diradical Reactions.- Some Comparisons of Types of Wave-Functions for 4-Electron 3-Centre Bonding Units.- A Note on Pauling ’3-Electron Bonds’ and Covalent-Ionic Resonance.- Valence-Bond Representations for 3-Electron 3-Centre Bonding.