You can view which flexfield segments or concurrent program parameters use a given value set with the Usages button on the Value Sets window.
To use this feature, you must first have privileges to the relevant flexfield segment or concurrent program parameter form. In particular:
You must have access to the Descriptive Flexfields Segments form to view the descriptive flexfields that use the value set.
You must have access to the Key Flexfields Segments form to view the key flexfields that use the value set.
You must have access to the Concurrent Programs (Developer Mode) or the Concurrent Programs (System Administrator Mode) form to view the concurrent program parameters that use the value set.
If you do not have access to any of the above forms, the Usages button is disabled.