The third edition of Theory of Simple Liquids is an updated, advanced, but self-contained introduction to the principles of liquid-state theory. It presents the modern, molecular theory of the structural, thermodynamic interfacial and dynamical properties of the liquid phase of materials constituted of atoms, small molecules or ions. This book leans on concepts and methods form classical Statistical Mechanics in which theoretical predictions are systematically compared with experimental data and results from numerical simulations. The overall layout of the book is similar to that of the previous two editions however, there are considerable changes in emphasis and several key additions including:•up-to-date presentation of modern theories of liquid-vapour coexistence and criticality•areas of considerable present and future interest such as super-cooled liquids and the glass transition•the area of liquid metals, which has grown into a mature subject area, now presented as part of the chapter ionic liquids•Provides cutting-edge research in the principles of liquid-state theory•Includes frequent comparisons of theoretical predictions with experimental and simulation data•Suitable for researchers and post-graduates in the field of condensed matter science (Physics, Chemistry, Material Science), biophysics as well as those in the oil industry