Did you know that it’s possible to find out what SMS classes will be assigned to a dataset without actually allocating it? The ISMF Test function allow users to specify dataset allocation characteristics and run the ACS routines in ‘test’ mode, without creating a dataset. The ACTIVE configuration can be used, or alternate set of ACS routines can be run to see what the result of an ACS change will be. We’ll discuss the ISMF Test facility provided by IBM, including the Naviquest feature, their functions, advantages, and disadvantages, and we’ll also take a look at DTS Software’s SMS Debug & Audit product which extends the functions of ISMF Test to make it more reliable and useful.