The document provides an overview of IBM's Automatic Binary Optimizer (ABO) for z/OS. ABO improves performance of compiled COBOL programs without requiring source code changes or recompilation. It optimizes directly from compiled binaries to generate code targeting the latest IBM Z systems. Early customer results show performance gains ranging from 5-21%. The tool supports debugging and works with IBM and third party performance analysis tools. It performs whole-program optimization while preserving compatibility. Customers can use ABO for static selection to load optimized modules or dynamic selection using product infrastructure for optimization configuration and tracking.