Understanding the fundamental science of the Fine Chemicals industry is necessary in the development of efficient, high-yielding and environmentally friendly processes. This is the first text to specifically address this topic by covering the physiochemical principles underpinning the subject. It outlines the strategy for obtaining the requisite data, and the chemical and chemical engineering concepts involved in process development. These include a description of pre-reaction equilibria in single and two-phase systems, factors influencing selectivity in competing reactions, mixing effects in single and two-phase reactions, the science behind workup processes and a discussion of the principles behind scale-up.