The data is seen as an important historical record
The Central Statistics Office (CSO) has launched its campaign for Census 2016.
The census will take place on Sunday, April 24th.
Everybody who spends that night in Ireland must be included on a census form.
The data collected will be free to use and can be used for a wide range of purposes - including the development of better public services.
It will also feed into the planning stages, such as schools, train lines and childcare facilities.
The census is also seen as an important historical record.
Speaking at the launch of the campaign, acting Taoiseach Enda Kenny outlined its importance.
"By participating in the census on the 24th April, each and every one of us will help to shape our understanding about life in Ireland today".
"We will also show how, as a country, we have changed and are changing over time. Importantly, it will also equip us to plan for the Ireland of tomorrow", he added.
Census forms will now be delivered by hand to every household in the State over the next five weeks, and will then be collected in person.
"The CSO rely heavily on the dedication and commitment of our census enumerators and field managers to do this work on our behalf," director-general of the CSO Pádraig Dalton said.
"I have every confidence that our 5,200 field staff will carry out this census with total professionalism and I'd like to take this opportunity to thank them in advance", Mr Dalton added.
For those whose first language is not Irish or English, a translation of the form is available in 21 foreign languages.
Other resources also available to assist people with filling out the census form include large print, braille and audio versions of the form.
A step-by-step video guide to completing the form - as well as more information - is available here.
Senior statistician at the CSO, Deirdre Cullen, says the census serves as a marker for progress.