Note:  Prior to January 2006 catalogers did not add a diacritic to initial capital letters in French, Spanish, and Portuguese.  This exception no longer applies.  With respect to capital letters appearing at the beginning of names or words, add diacritics according to the usage of the language.  When in current cataloging a change is otherwise needed to an existing bibliographic or name authority record in these languages, catalogers are asked to change the heading(s) to add the diacritic at the same time.  If there is insufficient evidence or some doubt as to the preferred usage, do not change the heading.

With respect to acronyms, initialisms (including single capital letters used in names), do not systematically add the accent.  Instead:

1.   for purposes of transcription, follow the usage as found in the data;

2.   for purposes of establishing the authorized form of a corporate name, follow the usage as found on the body's own publications.

See also:

1.0.  General Rules