The SYSLIB data set concatenation defines the macro libraries for the Cobol compiler and their order. Any number of macro libraries may be specified and any library that is a zFolder may be so flagged. Any libraries that do not already exist on the system can be specified too.

The following is a list of common libraries that may be considered for the SYSLIB concatenation:
| Cobol | |
| Library: | Description: |
| COPYBOOK | A zFolder Data Set Containing Copy Members |
| CICS.SDFHCOB | CICS COBOL Library |