In earlier chapters, methods of manufacturing and characterization of pharmaceutical particulate systems were described. It is evident that key physicochemical properties establish the foundation for quality and performance of a dosage form of which they are components. This is fundamental to monitoring and controlling of critical properties of these systems with a view to optimization, ideally establishing quality by design. The use of statistical experimental design during optimization and statistical process control during manufacturing allows the production of the dosage form to meet the target product profile within narrow limits, thereby assuring uniformity. Ultimately, the dosage form quality translates into a safe and efficacious drug product.