The shift in process validation from a one-time event to the product lifecycle approach expected by most global markets has led to significant changes in validation practices. The science and risk-based approach combines product development knowledge with a structured process performance and product quality monitoring system to provide for validation throughout the product lifecycle. In today's pharmaceutical industry, process validation relies on information and knowledge from product development activities to ensure patient requirements are translated into product attributes. A key to success is establishing a comprehensive science-based process design that focuses on understanding sources of variability. Translating the sources of variability into a well-designed control strategy that reliably ensures a product's attributes are attained may help achieve robust product realization. Covering a wide variety of manufacturing types, the ISPE Good Practice Guide: Practical Implementation of the Lifecycle Approach to Process Validation is a reference of technical and scientific detail to help organizations conduct process validation from scientifically sound development to robust reliable processes. It is intended to assist companies in understanding the application of global regulatory validation requirements by providing step by step implementation approaches to PV and leveraging process understanding to promote best practices. The use of statistical rationales within the different stages of the process validation lifecycle is explained. Case studies demonstrating the benefits of some of the Guide's practices in action are also included.