The 30th annual Christmas anti-drink-drive crackdown was launched today.
The aim is to stop the recent rise in the number of alcohol-related road deaths.
Police will be breathalysing huge numbers of motorists over the next four weeks, as well as looking out for drivers impaired by illegal drugs.
After last year's festive period campaign road safety groups called for a tough crackdown when it was disclosed that 9,275 motorists were caught over the limit in a month.
When figures were released in January, the Royal Society for the Prevention of Accidents renewed calls for the alcohol limit to be cut from 80mg to 50mg.
The proportion of motorists found to be over the limit after an accident in the 2005 crackdown was 8.6% of those tested, or 1,344, only slightly down from 8.75% last year.
'Fitness to drive' roadside tests on 540 motorists suspected of being impaired by illegal drugs led to the arrest of 178 people in the month, or 33% of those tested.
The campaign will run throughout December.