Imagine getting an invitation to an event only to be stopped in your tracks by the dress code. “Smart casual,” “business formal,” “black tie optional”—what do they even mean, and how do you avoid showing up underdressed or overdressed? Whether it’s a casual Friday at the office, a weekend cocktail party, or a formal wedding, understanding and mastering dress codes can make a world of difference. In this guide, we’ll explore the different levels of dress codes, offer styling advice for each, and show you how to build a wardrobe that’s flexible and ready for any occasion.