Police are targeting drink-drivers in a three-day blitz after 40 people died in NSW crashes last month.
October was the worst month for fatalities this year, with a quarter over the Labor Day long weekend.
Highway Patrol commander Superintendent Stuart Smith says people need reminding of the risks of drink-driving, particularly in the weeks before Christmas holidays.
"We're entering that period where people start to drink more," he said.
"What we're saying is, `Stay off the roads if your judgment is impaired'.
"The message is very clear - if you drink, don't drive. Chances are you'll be caught."
The three-day blitz will begin after midnight (AEDT) on Wednesday and run until midnight on Saturday.
Officers from 80 stations will assist highway patrol with random breath tests.
Senior Sergeant Mark Nielsen, a highway patrol officer of more than 30 years, said RBTs change people's attitudes towards drink-driving.
"Without a doubt, it has been the most prolific strategy that saves lives," he said.
"I've seen everything, but drink-driving is the worst because it kills innocent people."
