With the release of the "RSM Enablement Offering" on zEnterprise, IBM now offers internal flash memory for mainframe-class computing. In z/OS flash memory has been integrated within the memory hierarchy to provide higher levels of system availability and speed. With Flash Express the system can reduce workload and response time delays due to increased memory pressure during periods of peak demand, transitions between different workloads, or during collection of diagnostics. In this presentation, we will open up the covers to show how we have incorporated this exciting and rapidly maturing technology into our new server. We will reveal how the innovative system z Flash Express design provides for a superior system z level of reliability, availability, resiliency and security. In addition, this presentation will cover z/OS customer use cases and performance results to demonstrate when this function is best used and what the benefits would be.