What does a black-tie dress code actually mean?

For men-or women who want to dabble in suiting-the brief is pretty simple: black tie means you're to wear a black bow tie with your dinner jacket. Because it's a step down in fanciness from white tie, the black-tie dress code leaves more room for interpretation when it comes to garments beyond the suit-but there are still certain parameters. While one woman's "dress to impress" may mean a barely there Mugler minidress, that would be entirely wrong for a charity gala (though definitely impressive!). So, in moments of doubt, don't be afraid to ask your host for clarification on the level of formality they are expecting of their guests-as well as intel on what they themselves are planning to wear.