Experiments before World War I -- W.H. Carothers - Life and Work -- P.J. Flory and the Theory of Step-Growth Polymerization -- W. Stockmayer and the Role of Equilibration -- Important Polycondensates -- The Role of Cyclization and a new Theory of Step-Growth Polymerization -- Non-Stoichiometric Polycondensations -- Ring-Opening Polycondensation -- Multibranched Polymers by a2 + bn Polycondensations -- Hyperbranched Polymers by abn Polycondensations -- Multicyclic Polymers -- Polycondensations via Electrostatic Interactions -- Solid State Polycondensations -- Combined Ring-Opening Polymerization and Polycondensation -- Condensative Chain Polymerization.