Introduction: Karl K. Irikura and David J. Frurip, computational thermochemistry. Part 1 Empirical methods - group contributions: S.W. Benson and Norman Cohen, current status of group additivity; Eugene S. Domalski, estimation of enthalpies of formation of organic compounds at infinite dilution in water at 298.15 K - a pathway for estimation of enthalpies of solution; James S. Chickos, William E. Acree, Jr. and Joel F. Liebman, estimating phase-change enthalpies and entropies. Part 2 Empirical methods - other approaches: Hussein Y. Afeefy and Joel F. Liebman, estimation of the enthalpies of formation of organic compounds in the solid phase - the study of 2-acetoxybenzoic acid (aspirin) and its isomers; R.S. Drago and T.R. Cundari, electrostatic-covalent model parameters for molecular modelling; Donald W. Rogers, molecular mechanics in computational thermochemistry. Part 3 Methods based on molecular-orbital or density-functional theory: Walter Thiel, thermochemistry from semiempirical molecular orbital theory; Michael R. Zachariah and Carl F. Melius, bond-additivity correction of ab initio computations for accurate prediction of thermochemistry; Larry A. Curtiss and Krishnan Raghavachari, computational methods for calculating accurate enthalpies of formation, ionization potentials, and electron affinities; Margareta R.A. Blomberg and Per E.M. Siegbahn, calculating bond strengths for transition-metal complexes; Jan M.L. Martin, calibration study of atomization energies of small polyatomics; George A. Petersson, complete basis-set thermochemistry and kinetics; Joseph L. Durant, computational thermochemistry and transition states; David J. Giesen, Candee C. Chambers, Gregory D. Hawkins, Christopher J. Cramer and Donald G. Truhlar, modelling free energies of solvation and transfer. Part 4 Applications: J.T. Golab and M.R. Greenlied, practical chemistry modelling applied to process design studies; David J. Frurip, Nelson G. Rondan and Joey W. Storer, implementation and application of computational thermochemistry to industrial process design at the Dow Chemical Company; R.J. Berry, M. Schwartz and Paul Marshall, ab initio calculations for kinetic modelling of halocarbons; Peter Politzer and Jorge M. Seminario, use of density functional methods to compute heats of reactions; Tom Ziegler, periodic trends in bond energies - a density functional study. Appendices: David J. Frurip and Joey W. Storer, software and databases for thermochemistry; Karl K. Irikura, essential statistical thermodynamics; Karl K. Irikura and David J. Frurip, worked examples; Karl K. Irikura, glossary of common terms and abbreviations in quantum chemistry.