Announcing the latest lockdown, Taoiseach Micheál Martin said tighter restrictions are needed to fight what he called "a deadly and ever-changing virus".
The Government has ordered people to stay at home and warned that we may be entering the most challenging period since the outbreak of the pandemic.
The new measures include:
The 5km travel limit is to be maintained and people have been asked stay at home and work from home where at all possible.
However, new measures requiring all those entering the country via air or sea to show a negative Covid test are to be rolled out from the weekend starting with people coming from the UK and South Africa.
In the meantime, the travel ban from both countries is to remain in place.
Schools are to remain closed until the end of this month, however Leaving Certificate students will attend class three days a week.
An exception has also been made for special education schools and special classes in mainstream schools, with the Taoiseach claiming the in-class education of both groups has been deemed essential.
All other teaching will move online.
Education Minister Norma Foley had strongly argued that Leaving Cert pupils should be allowed to attend school to ensure they are prepared for the State examinations later this year. Pupils will therefore return for three days each week from January 11.
However, the details of this will now have to be worked out with unions as teachers will be expected to combine in-class learning for Leaving Certificate groups with online education for other year groups.
School transport will be available for all students attending school.
Higher and Further education will move online, except where a project is essential or time sensitive such as lab work.
Creches will be permitted to stay open for the children of essential workers only.
A household of an essential worker, without an existing childcare arrangement, can form a bubble with another household for the purpose of providing childcare.
The Early Childhood Care and Education (ECCE) Scheme will also halted until the end of the month.
The majority of the country's 200,000 construction workers will impacted by the latest restrictions as as sites close across the country from the end of the week.
All building sites will stay open until 6pm on Friday, however, after that only projects deemed as essential will be allowed to continue.
This includes vital infrastructure projects such as new schools and water services as well as social housing. Construction will also be allowed to complete urgent repairs
Head of the Construction Industry Federation (CIF), Tom Parlon said 5,000 homes had not been built and output had dropped by 10% during the last lockdown at a cost of €3bn to the industry and the economy.
Non-essential retailers have been ordered to immediately halt click and collect services. However, online shopping where items are delivered will still be allowed.
The Pandemic Unemployment Payment (PUP) and the Employment Wage Support Scheme (EWSS) will remain in place at current rates until the end of March. Weekly payments for businesses forced to close will also continue.
The Government is consulting with the banks on mortgagee breaks for those who are struggling as a result of the pandemic.