The gardaí's bank holiday road safety campaign came into effect at midnight last night.
Operation Lifesaver is aimed at reducing road deaths by cracking down on drink-driving, speeding, the non-wearing of seat belts.
Gardaí said checkpoints would be in place throughout the country as part of the campaign, with a particular focus on accident black-spots.
A total of 302 people have died in road accidents so far this year, an increase of 27 on the figures for the same period last year.