Karen,
It's convenient, IMHO, to have the most important use of <titleInfo> be
the simplest or default case, i.e. the main title of the work is in an
unqualified <titleInfo> while "extra" titles require setting the type
attribute.

Ruth,
In the MARC to MODS mapping on the website, both 772 "supplement
parent" and 773 "host item" map to <relatedItem type="host">, suggesting
that "host" in MODS has broader meaning that the word might imply.

--Andy

>>> [log in to unmask] 2004-01-21 17:01:03 >>>

Ruth, I too like the idea of there being a designated "main" title,
primarily because the main title is often a kind of identifier for the
item (along with things like author/date). I think of the "main" title
as being close to the "work" concept in ISBD and FRBR, and definitely
needed to identify the work.