If the invitation says…Then you should wear…Black Tiedinner clothes (tuxedo)

For Men
White Tie evening clothes (white tie/tails)
Black Tie Optional a tuxedo or dark suit
Semiformal a dark suit
Festive Informal a suit and brightly colored tie
Cocktail Attire a dark suit or dressy sports coat
Business Attire a suit and tie
Business Casual a sports coat; tie is optional
Casual Chic a sports coat or sweater & slacks
Casual jeans, chinos or shorts

Black Tielong gown, cocktail dress, or long skirt and dressy blouse (tuxedo)

For Women
If the invitation says… Then you should wear…
White Tie long ball gown
Black Tie Optional cocktail dress or suit, skirt & dressy blouse or slacks & dressy blouse
Semiformal cocktail dress
Festive Informal casual sportswear outfit with a “twist,” dressy blouse & pants, ruffle bloused & tea length skirt
Cocktail Attire cocktail dress or little black dress, dinner suit
Business Attire skirt or pant suit, work dress
Business Casual slacks or skirt with sportswear jacket or sweater
Casual Chic dress jeans with fun blouse or sweater