REXX/CICS includes as one of its basic facilities, the ability for systems administrators and users to easily and dynamically define new REXX commands, either on a system-wide or user-by-user basis. One of the greatest strengths of REXX is its ability to interface cleanly with other products, applications, and system services. The goal for providing a command definition facility for new or existing commands is to facilitate the rapid and consistent high-level integration of various products and services together through the use of REXX. REXX command definition is accomplished with the REXX/CICS DEFCMD and DEFSCMD commands.