Root context has been a well-known concept. I did a search on root context (and on root-context). It is not defined. It is mention in Annex S of X.501 (Part 2), an annex added in the fifth edition and in X.519 (Part 5) in the conformance clause. Any explanation? Erik Andersen Andersen's L-Service Elsevej 48, DK-3500 Vaerloese Denmark Mobile: +45 2097 1490 email: era@xxxxxxx www.x500.eu www.x500standard.com