The only time I absolutely 100% had to dress black tie was to sit at the captain's table and attend a couple of other events on a cruise, but I have been to black tie optional events, law firm christmas dinners to be exact. I bought my dinner suit (tuxedo) for the cruise, not knowing that they had rentals on board, and wore it to the black tie optional christmas dinners, often outshining senior partners that went in a lounge suit, which may have been bad office politics! My present law firm doesn't go in for even a black tie optional event, probably because it is very small.

I have nothing formal to go with my kilts, because I can't imagine getting invited to anything where I could wear black tie more than once a year at most, and I already own the trousered equivalent, which gets very little wear as it is.

Pity really, as I have my eye on a dress sporran with the English (St. George's cross) flag on it. Can't think where I'd ever wear it. But don't the Irish hate the English, you might say? Well, I'm a mixture of both, you see.

As for white tie, I just don't think I move in those sort of circles. ETA: No I didn't see the post above! Great minds think alike.