"We're not serving liquor," on invites

• Letters on a party invitation indicating that booze won't be provided by the host
• Brown-bagging letters
• "I'm not providing, you drunks!"
• Drinker's party instruction, for short
• Informal invitation letters
• Inits. on an invitation
• BBQ invite letters
• Abbr. often preceding 29-Down

Wikipedia Word definitions in Wikipedia
BYOB is an initialism used on party invitations, meaning "bring your own beverage" or variants. BYOB may also refer to: BYOB (musician) , an English musician B.Y.O.B. (song) , a song by System of a Down from their album Mezmerize BYOB (programming language) ...