When you define a group, you should consider the basic purpose of the group. Is it an administrative group, a holding group, a data control group, a functional group, or a user group?

When setting up RACF® groups, keep in mind that the maximum number of users that you can connect to any one group is approximately 5900. See the topic on determining storage requirements for profiles in z/OS Security Server RACF Macros and Interfaces for information about how to determine the exact maximum number.

For groups that might become large, and for which a quick listing of members is not needed, you might want to consider defining the groups using the UNIVERSAL operand of the ADDGROUP command. Universal groups might be appropriate for holding groups and other types of groups. See Defining large groups with the UNIVERSAL attribute.