FACT: THE AVERAGE 7 DAY CRUISE FEATURES 2 FORMAL EVENINGS ... On some cruises as many as four! Sure, you could "get by" with a dark business suit or you could "rent" a tux from your local men's shop. Let's face it. Business suits are boring and renting for a week plus tends to be quite expensive. It would be economical to purchase your tuxedo since the purchase price these days are usually the same cost as renting if not less. Plus, most rental companies charge a surcharge for extended rentals. Shop around. You'll see what we mean. Any tuxedo, with the exception of tails, is perfect for either of the "formal" evenings on your trip. Plus, adding a white or ivory dinner jacket to your wardrobe as a second outfit is an excellent idea. Mix and match this and that and your all set! P.S. - Going as a couple? Be sure to find out what color they will be wearing as well. Going to a formal on a cruise is no different then going to a wedding. Both parties should match!