One person was killed yesterday and over a dozen people were injured in a number of serious crashes, two of which involved buses.
In Westmeath, a man was killed and a mother and daughter were seriously injured as a result of two early morning accidents near Delvin.
The dead man has been named as Dan Hynes (22), a construction worker from Tulsk, Boyle, Co Roscommon.
He was in the rear of a Ford Transit van involved in a crash on the N52 just outside the town.
Gardaí said that as the van reached a bend approaching Delvin at the townland of Clonyn at about 7.10am, it spun out of control and struck a wall, before spinning back on to the road into the path of an oncoming 4x4 Toyota Landcruiser.
Gardaí confirmed they had received reports of an oil spill on the road earlier in the morning, which they passed on to Westmeath County Council.
Mr Hynes was one of a number of men in the van travelling to Castlebellingham for a construction job.
Just after the Delvin crash, as the emergency services left the scene, they were summoned to another serious accident just three miles away.
A woman and her daughter travelling in a Toyota Yaris struck a cement lorry on the Delvin-Killucan road at Bracklyn, shortly before 9am.
Emergency personnel found the teenager sitting on a grass verge on the side of the road with serious head injuries.
Her mother was trapped inside the car. Mullingar fire brigade personnel freed the woman and both were taken to the Midland Regional Hospital in the town where their injuries were described yesterday as not life threatening.
At about the same time in Roscommon, seven teenagers on their way to the National Ploughing Championships in Tullamore, Co Offaly, were injured when their minibus collided with a car at Lisagallon near Cloverhill, on the Roscommon-Castlerea road.
The teenagers all suffered minor injuries, while the driver of the car was described as seriously hurt.
Two men were injured later when a bus collided with a lorry shortly after 2pm in Westmeath, on the outskirts of Moate on the Killbeggan road.
Both drivers are in a stable condition in the Midlands Regional Hospital in Tullamore, Co Offaly. There were 27 people in the bus at the time of the crash, but nobody else was injured.
Meanwhile, the victim of Monday's fatal road traffic collision at Kildimo, Limerick, has been named as Mark Ryan (20), Bawnreagh, Askeaton, Co Limerick. Mr Ryan's car was in a collision with an articulated lorry.
On Sunday, Mary McGuane (75) was killed after being hit by a motorcycle near Ennis, Co. Clare. The night before, Seán Devine (19) was killed after he was hit by a van when cycling outside Newbridge College in Co Kildare.