The best discussion I’ve ever seen of legal letterhead. What’s more, Mr. Butterick wastes not a lone syllable:
Picture a sheet of letterhead. What’s in the foreground? If you said “the address block,” then I’m guessing you pictured a blank sheet of letterhead. But letterhead is never used blank. So more accurately, the foreground contains the text of the letter. The background contains the address block.
Yet lawyer letterhead often suffers from two problems. First, the address block (the background) dominates the page, upstaging the text of the letter (the foreground). Second, the foreground and background don’t relate to each other visually.
Taken from the page “Letterhead,” on the website Typography for Lawyers.
Mr. Butterick is also the author of a book by the same name (Typography for Lawyers, not Matthew Buttterick, whose eponymous website can be found at ButterickLaw.com.