Relentlessly prowling the internet for information on formal and semi-formal dress, Peter Marshall of the Black Tie Guide, by far the most informative and accurate web site on those topics, calls our attention to an online booklet called Dress Codes. Dress Codes is a guide to dress for the Viennese ball season, the principal remaining home of formal evening dress for men in the Western world (although it is mandatory at only two of the 26 balls mentioned specifically).
Recalling as they do another time, in 2010 UNESCO named several of the Viennese balls as part of the world's intangible cultural heritage, and, recognizing the lack of information on proper formal and semi-formal dress, the organizers published Dress Codes to help keep international guests from arriving in a business suit (or a cocktail dress as the guide is aimed at both men and women). This is particularly useful for white tie, where aside from Black Tie Guide there is little information available on the proprieties. It is interesting reading, however I did notice that it neglects to mention the lead times involved for acquiring well made formal clothes. As Simon Cundey of Henry Poole told me a while ago, the tailcoat is one of the most complex garments known to tailoring and requires at least two and preferably three fittings instead of the usual one that bespoke customers are accustomed to.
Gentlemen thinking of attending the Viennese season take note.