While we want our event to be formal, we understand that Black-Tie wear is not always possible. We ask that our guests dress in Black-Tie optional wear instead. For men, this looks like a suit or tux. For women, this looks like a floor-length dress or equivalent.

Here is further detail:

"Black-tie optional weddings are slightly less formal than nuptials with black-tie attire, so they allow for a little more flexibility in the formality of guests' ensembles. With this dress code, tuxedos aren't required, but men can still wear a tux if desirable. Otherwise, they can select a formal suit and tie. For women, floor-length gowns are still encouraged..." (Brides.com).