This monograph presents the molecular theory and necessary tools for the study of solvent-induced interactions and forces. After introducing the reader to the basic definitions of solvent-induced interactions, the author provides a brief analysis of the statistical thermodynamics. The book thoroughly overviews the connection of those interactions with thermodynamics and consequently focuses on specifically discussing the hydrophobic-hydrophilic interactions and forces. The importance of the implementation of hydrophilic interactions and forces in various biochemical processes is thoroughly analyzed, while evidence based on theory, experiments, and simulated calculations supporting that hydrophilic interactions and forces are far more important than the corresponding hydrophobic effects in many biochemical processes such as protein folding, self-assembly of proteins, molecular recognitions, are described in detail. This title is of great interest to students and researchers working in the fields of chemistry, physics, biochemistry, and molecular biology.