This text discusses the functions of Process R&D (research and development), which involves the method of transforming a research synthetic procedure into a plant process and the key aspects of a synthesis that must be considered when scaling up a process. Topics consist of: basic principles of chemical development; techniques for the minimization of by-product impurities; criteria for cost-effective synthesis of enantiopure compounds by resolutions; asymmetric synthesis, and "chiral pool" strategy; synthesis for labeling substances with hydrogen or carbon isotopes; and last, licensing.