Bultinck (computational chemistry, Ghent University, Belgium) collects techniques used by industry and academia for ligand design. Contributors survey molecular structure computation, intermolecular behavior, ligand-receptor interaction, and modeling. Early chapters are devoted to methods for the computation of molecular structure, and later chapters describe aspects of molecular behavior in terms of properties such as electrostatic potential, nonbonded interactions, and behavior in solvents. An evaluation of protein structure determination is followed by accounts of docking and scoring, pharmacophore identification 3D searching, and molecular descriptors. Further chapters cover 2D and 3D models using classical molecular and quantum-based descriptors and models derived from data mining techniques and library design.