Choose the Collection... submenu item to create a
  set of files that DTM uses to run the tests in the
  collection.

  A collection can contain noninteractive tests,
  interactive terminal tests, and DECwindows tests in
  any combination.

  DTM constructs the set of tests in the collection
  by taking a "snapshot" of the test descriptions when
  you create the collection. If you subsequently change
  any of the test descriptions, you must re-create the
  collection.

  Changes made to files referenced by the collection do
  affect the collection at run time.