New research suggests people sick of waiting to be served at a bar can speed things up with their body language and by looking directly at serving staff.
The findings, from Bielefeld University in Germany and published in the Frontiers in Psychology journal, say getting served ahead of others at a busy bar is down to body language and concentrating on winning the attention of those pouring the drinks.
Patrons sidling up to bars between other customers were often left waiting longer, as were those who divided their attention by chatting with friends or perusing menus.
Holding a wallet or purse had some success, but gesturing with a hand or head to a bartender was less effective, reported scientists after observing 105 bids to order drinks at three German and Scottish nightclubs.
Lead researcher Sebastian Loth said customers identified themselves as ordering or non-ordering patrons through their behaviour.