We provide a somewhat historical perspective on the work that has been accomplished that supports the suggestion of phase transitions in reversed-phase liquid chromatographic bonded phases. In addition to this general review, we consider from both a practical and theoretical viewpoint the implications of such transitions in the rational design of improved reversed-phase separations. Analytical theory and molecular simulation approaches to chromatographic stationary phases and related systems are reviewed. Initial results are presented on the temperature, density and chain length dependences of stationary phase properties. The role of computer simulation in analyzing transition behavior and retention processes is discussed.