This chapter presents the process of upfront corrective maintenance at the front-end support level. The chapter is logically divided into two parts. The first part introduces the domain of the upfront corrective maintenance process, and presents its current status practiced in the industry. It first describes the process, places it within a global virtual IT enterprise and explains its role within the enterprise. It then puts the process in the context of a total front-end support process, the process performing a multitude of diverse types of support activities. Finally, it lists the problems encountered by the front-support organisations today. The second part provides a glimpse into Corrective Maintenance Maturity Model (CM3): Upfront Maintenance, a process model specialized in upfront corrective maintenance. It describes its process phases, maturity levels, and collaboration with the CM3: Problem Management model, a problem management process model at the back-end support level. The goal of this chapter is to provide a detailed insight of the process of upfront corrective maintenance.