During the operational life of a GxP system regulators usually focus on the integrity, consistency, and completeness of controls required to maintain compliance. This Guide highlights the importance of the operation phase of the system lifecycle, when the return on investment for the significant time and resource expended in implementing new computerized systems can be achieved. The Guide will help regulated organizations achieve regulated computerized systems that are fit for intended use and compliant with applicable regulations and provides comprehensive guidance for maintaining control of regulated systems throughout their operational life.