System and private libraries can contain both procedures and INCLUDE groups. The order in which the system searches system and private libraries for INCLUDE groups is the same as the search order used for procedures (see Using a procedure).

Do not define procedures in an INCLUDE group. However, you can put EXEC statements that invoke procedures in an INCLUDE group.

You can use INCLUDE statements to imbed INCLUDE groups that contain DD and OUTPUT JCL statements, which allows you to use the same data set definitions for various jobs.

When the INCLUDE statement and the INCLUDE group contain symbolic parameters, the system substitutes the values that are current at the time the symbolic parameter is encountered. Values assigned to symbolic parameters in an INCLUDE group (such as with the SET statement) are valid for use on subsequent JCL statements.