Shorts, T-shirts, short-sleeve shirts, and sweatshirts are not allowed, let alone flip-flops, so if you've spent the day exploring Monte Carlo, be sure to change before. Pro Tip: Some rooms require men to wear a jacket.

Casinos tend to be more casual during the day than at night. Males should stick to collared or button-down shirts and women should wear blouses and other formal clothes. After sundown, it is best to avoid wearing shorts and t-shirts. The higher the status of the casino, the more formal you should dress.