A brief summary of quantitative structure-property relationship methodology, together with an explanation of the approach using theoretical molecular descriptors to study diverse physical, chemical, and technological properties of organic compounds, is given. Studies of several properties of importance to fuels science are described including (i) physical properties of single molecular species (e.g., boiling points, melting points, refractive index), (ii) properties involving interactions between different molecules (e.g., critical micelle concentration, flash points, solvent effects, free-radical polymerization, vulcanization of rubber), (iii) solution properties (e.g., solvent polarity, solubility, chromatography), and (iv) biological properties, (e.g., toxicity). Future objectives of interest to fuel scientists are discussed.