There will be an increased Garda presence on roads around the country.
Ireland's highest level of public health measures came into effect at midnight on Wednesday and will be in place for a period of six weeks.
The government said the action is based on current public health advice and the deteriorating situation with Covid-19 across the country.
People are asked to stay at home and should work from home unless providing an essential service for which their physical presence is required.
All non-essential retail has closed but schools and childcare facilities will remain open.
A full list of all the restrictions can be viewed
here.
A "high visibility" Garda operation has also commenced as the country moves into Level 5.
The 132 static checkpoints on motorways introduced earlier this month will remain in place, and will be supplemented by hundreds of rolling checkpoints on main and secondary roads.
Garda Commissioner Drew Harris said: "There was very good compliance by the public with the travel restrictions when they were in place before. It is vital that we see that high level of compliance again this time. The public health advice is clear. This will help save lives.
"In particular, we would ask people to think about their journeys and not exercise or travel outside the 5km limit unless it meets the essential criteria.
"An Garda Síochána is continuing with our graduated response based on our tradition of policing by consent.
"This is a difficult time for everybody, but if we all work together we can reduce the spread of Covid and protect our families, friends and neighbours."
1,167 cases of Covid-19 were confirmed on Wednesday, with cases in every county. 314 people are in hospital with Covid, while 34 people are in ICUs across the country.
Dr Tony Holohan, Chief Medical Officer, Department of Health, said: “The behaviour of every individual is the most effective defence we have against the spread of Covid-19.
“Everyone needs to stay at home, other than for essential reasons. Follow the public health advice and treat everyone that you come into contact with as though they are a close contact of someone with Covid-19 – keep your distance, avoid meeting others.
"We are facing a big challenge, but we have faced this challenge before, and that means we know how to suppress this virus, by following the public health advice in everything we do.”
