This manual is a users manual for the NIST DMIS Test Suite, version 2.2.1. The test suite is intended to serve two purposes: to help users and vendors use version 5.2 of DMIS (the Dimensional Measuring Interface Standard) and to provide utilities and test files for conducting conformance tests on, DMIS input files, computer systems that generate DMIS input files, computer systems that execute DMIS input files.