CUNUNI contains information that the system needs to activate, replace, or delete z/OS Unicode conversion environments. The conversion environment is set up to create a conversion image that is loaded into storage. The conversion image will contain the conversion tables that define the data conversions allowed between CCSIDs. For information about creating this parmlib member, see z/OS Unicode environment and CUNUNIxx in z/OS MVS Initialization and Tuning Reference.