Martin McGuinness resigns as deputy first minister of Northern Ireland following a "cash-for-ash" scandal involving first minister Arlene Foster of the DUP. The move plunges the political process into a year of chaos. McGuinness, undergoing medical treatment, later retires from active politics.
Bus Éireann staff are warned of a threat the company will become insolvent within the next 18 months and that a change in its business model is necessary due to strong competition. The company subsequently introduces cost-saving cuts.
A month after being occupied by homeless people and campaigners, Apollo House in Dublin’s south inner city is vacated.
Minister for Education Richard Bruton announces plans to remove the "baptism barrier" from schools to ensure children from non-religious backgrounds are not discriminated against by admission policies.
UK prime minister Theresa May confirms Britain will leave the single market after Brexit and rules out full membership of the customs union in a speech to foreign diplomats at Lancaster House in London. Controls on the Border appear likely to return.
Three people are arrested at Dublin Airport on suspicion of assisting immigrants to illegally enter the country by getting around security controls.
European competition commissioner Margrethe Vestager says she believes Apple owes Ireland virtually all of the €13 billion in back-taxes the EU had ruled the Government must collect.
BAM Ireland, one of the State’s largest building contractors, is awarded the contract to build the national children’s hospital in Dublin at a price close to €1 billion, €300 million more than the original budget of €650 million.
The Garda Commissioner Nóirín O'Sullivan faces an unprecedented commission of investigation following allegations she attempted to blacken the name of Garda whistleblower Maurice McCabe. O'Sullivan, who continues to deny the accusations, will be assessed by Supreme Court judge Peter Charleton.
A Government-commissioned review recommends cannabis should be made available to treat a limited number of medical conditions.
The average cost of renting a home reaches the highest level on record, climbing faster than at any point since figures began in 2002.
Pressure builds on Taoiseach Enda Kenny, who even faces the prospect of a leadership challenge, over his failure to give a firm indication of when he will step down.
Drink-driving checkpoints are to be audited across the State following revelations of discrepancies in the number of breath tests recorded by gardaí.
Sinn Féin makes major gains in Northern Assembly elections, dramatically narrowing the gap between it and the Democratic Unionist Party. But difficulties quickly emerge in reinstating a Stormont administration.
Martin McGuinness dies of a rare heart condition and is laid to rest in his native Derry.
Gardaí confirm they are liaising with the coroner's office in north Galway after the remains of "several hundred" infants are found at a former home in Tuam. The Commission of Investigation into Mother and Baby Homes says it is shocked by the discovery.
Former bishop of Galway Eamonn Casey dies following a battle with Alzheimer's.
Irish Coast Guard helicopter Rescue 116 crashes off the north Mayo coast as it approaches Blacksod lighthouse to refuel. Its crew – Dara Fitzpatrick, Mark Duffy, Ciarán Smith and Paul Ormsby – are all lost.
Minister for Transport Shane Ross signals his intention to introduce laws automatically disqualifying drink-drivers and meets political resistance.
An indefinite Bus Éireann strike begins, causing travel disruption to about 100,000 passengers.
The Fennelly commission, set up to investigate the recording of phone calls by gardaí, finds a massive programme in stations around the State was set up by mistake and operated in ignorance, but not abused.
The Government decides against extending the institutional child abuse redress scheme to those who lived in mother and baby homes as unaccompanied children as it could cost as much as €1 billion.
A long-awaited deal is announced making life-saving drugs available to up to 600 people with cystic fibrosis. After nine months of negotiations, the HSE and Vertex Pharmaceuticals reach an agreement for the supply of the drugs Orkambi and Kalydeco.
Fianna Fáil calls on the Government to set aside money for water charge refunds in October's budget. The move follows the publication of the final report of the Oireachtas committee on water charges, which recommends a refund.
A report into the crash of Coast Guard helicopter Rescue 116 finds its crew was using a pre-programmed route that appeared to be deficient in information. The preliminary Air Accident Investigation Unit report says the helicopter "pitched up rapidly" and hit the western end of Blackrock Island in its final seconds.
Minister for Health Simon Harris promises there will be no "religious interference" at the National Maternity Hospital, rejecting claims the Sisters of Charity order, who will own the new facility through their ownership of the land at the St Vincent's site, had been "gifted" the hospital.
The remains of Séamus Ruddy are discovered in a forest in France. One of the so-called "Disappeared", the 33-year-old was a former member of the Irish National Liberation Army's political wing and teaching in Paris in 1985 when he was killed.
The average cost of renting a home in Ireland is found to have increased by €134 a month over the previous year, with prices in Dublin climbing by substantially more.
Further pressure mounts on Garda Commissioner Nóirín O'Sullivan after it emerges senior gardaí sought to cover up financial irregularities at Templemore Garda College for decades. Documentation compiled by John Barrett, the Garda's head of human resources, outlines significant concerns over financial practices at the college. It later emerges O'Sullivan delayed informing the Garda's internal audit unit after being instructed to do so by the Department of Justice.
Brexit will have a sizeable potential economic impact on Ireland, particularly on employment in rural areas, the International Monetary Fund (IMF) says in what is seen as one of the starkest warnings to date from an international body on the UK's decision to leave the EU.
Enda Kenny announces his intention to step down as Fine Gael leader, clearing the way for a battle between Simon Coveney and Leo Varadkar to succeed him. Varadkar immediately opens a commanding lead, attracting support from a large number of TDs and senators. In a poll, voters back Coveney.
Circuit Court Judge John Aylmer directs a jury to acquit former Anglo Irish Bank chairman Seán FitzPatrick of 27 charges under the Companies Act. It had been the longest criminal trial in Irish history. The judge says the Office of the Director of Corporate Enforcement (ODCE) had set out to "build or construct a case" against FitzPatrick rather than investigate it "independently and impartially".
Leo Varadkar bests Simon Coveney to become leader of Fine Gael and presumptive taoiseach. In victory he declares that “prejudice has no hold on this Republic”.
Controversy builds around the manner in which former attorney general Máire Whelan was nominated to the Court of Appeal, a move seen as being pressed by Enda Kenny as he left office. It emerges three High Court judges had expressed an interest in the post.
AIB returns to stock markets in Dublin and London after more than seven years in State ownership. About 6,500 small Irish investors buy shares, spending an average of €46,150 each on what is Europe's largest initial public offering (IPO) so far in 2017.
Theresa May reaches a deal with the Democratic Unionist Party (DUP) to prop up her government in Westminster by providing an additional £1 billion (€1.14 billion) in spending for Northern Ireland. The agreement, which would see the Conservatives retain a parliamentary majority following a calamitous general election, was finalised after more than two weeks of negotiation.
The Central Statistics Office suspends its publication of crime figures until a Garda review of homicide data is completed.
Solidarity TD Paul Murphy is warned by the Director of Public Prosecutions (DPP) about using his Twitter account to comment on the ongoing Jobstown trial. Murphy and five others were ultimately acquitted of charges of falsely imprisoning former Labour Party leader Joan Burton and her then assistant, Karen O'Connell, in Dublin in 2014. Mr Murphy had 14,300 followers on Twitter at the time of the trial.
The latest round of talks aimed at reinstating the Northern Executive and Assembly falter. Talks are “parked” for the summer, furthering concerns about the future of devolution.
Former IRA member Michael Christopher Hayes (69), from south Dublin, confesses to being part of the group responsible for the 1974 Birmingham bombings in which 21 people were killed. He refuses to identify those who placed the bombs in the Mulberry Bush and the Tavern.
Central Statistics Office (CSO) figures show Irish house prices increased by 11.9 per cent in the year to the end of May, with the rise in values outside Dublin outpacing those in the capital. A separate report by Daft.ie shows the most expensive area in the State in which to buy property is Sandycove in south Dublin.
The first of over 8,500 appeals by motorists wrongly convicted and fined for fixed-charge driving offences begin in courts across the country. They follow a Garda admission earlier in the year that 147,000 motorists had been wrongly summonsed to court for road traffic infringements.
The mother of Sophie Toscan du Plantier describes a decision by the High Court not to extradite Ian Bailey to face trial in France as "simply scandalous". It is 21 years since Ms Toscan du Plantier was killed.
Molly Martens Corbett is convicted of the murder of her Limerick-born husband Jason Corbett following a trial in Lexington, North Carolina, in the US. Her father, Thomas Martens, a former FBI agent, is also found guilty and both will serve between 20 and 25 years in prison.
Gardaí begin a major excavation of an overgrown plot of land in Chapelizod, Dublin in search of Trevor Deely, who disappeared after a night out in Dublin 17 years ago. The search ends unsuccessfully in September.
The Simon Community warns that the number of homeless people in Ireland could reach 10,000 by the middle of 2018 unless action is taken. The charity says the State's response was coming at far too slow a pace.
The British government says it envisages no customs posts on the Northern Ireland Border post-Brexit. Border posts, an official says, would mean a return to “the past and are completely unacceptable to the UK”.
The northwest is devastated by flash floods. Kevin “Boxer” Moran, Minister of State for the Office of Public Works, says the Government must “substantially” increase its €430 million budget for flood defences.
Gardaí say more than 30 lives have been saved in the past 18 months since the Kinahan/Hutch feud erupted in Ireland. The latest figure of related deaths is put at 12.
A British guarantee to preserve free movement of all European Union citizens between Ireland and the UK is seen as a significant breakthrough in the Irish strand of Brexit negotiations. Border trade questions remain.
Cabinet approves water charges refund to nearly one million householders who paid the controversial levy. The refunds will cost about €173 million but will draw a line under the long-running controversy.
Garda commissioner Nóirín O’Sullivan unexpectedly resigns, ending a near-three years in office dogged by controversies.
Newstalk presenter George Hook is suspended from duties following controversial remarks he had made about rape.
As Ireland’s housing crisis continues, a Government report finds it is not financially viable for builders to construct “affordable apartments” with sale prices of between €240,000 and €320,000.
JP Donleavy, author of The Ginger Man, dies at his home in Mullingar, Co Westmeath at the age of 91.
Ryanair sparks travel chaos when it announces its intention to cancel between 40 and 50 flights a day for six weeks due to a backlog of annual leave for its crews.
Ibrahim Halawa is cleared of all charges following 1,497 days in an Egyptian prison and up to 30 trial adjournments.
Former Irish Times sports journalist Tom Humphries is sentenced to 2½ years in prison for the defilement and sexual exploitation of a child. Humphries had exchanged more than 16,000 texts with a young girl he had groomed.
Former taoiseach Liam Cosgrave dies at the age of 97. Cosgrave, son of WT Cosgrave, had led the Fine Gael-Labour coalition from 1973 to 1977.
The Government estimates a new 6 per cent rate of stamp duty on sales of commercial property will raise an extra €376 million a year, as it passes Budget 2018.
A Commercial Court ruling clears the way for a new €850 million Apple data centre near Athenry, Co Galway.
Growing controversy engulfs financial institutions found to have wrongly removed homeowners from tracker mortgages. The Central Bank publishes new figures showing 12,500 customers were affected by the end of June.
Ireland is braced for Storm Ophelia. Schools and third level colleges are closed, hospital appointments are cancelled and people are advised not to travel. It is the worst storm in over 50 years, claiming three lives and causing widespread damage.
Ibrahim Halawa is finally released from prison, a month after his acquittal by an Egyptian court. He returns to Ireland days later.
Thousands of commuters are hit by the first in a series of planned Irish Rail strikes.
Allegations emerge of sexual harassment and bullying at the Gate Theatre by its former director Michael Colgan. An investigation is opened.
Details emerge of plans by Minister for Transport Shane Ross, Minister of State at the Department of Business John Halligan and Minister of State with responsibility for disabilities Finian McGrath to visit North Korea. The much-ridiculed idea never goes ahead.
The Paradise Papers story breaks. Among other things, the documents show how AIB had helped Ireland’s wealthy put their money offshore and avoid taxes. The bank seeks such business even after a taxpayer guarantee in 2008 and subsequent State rescue at a cost of €7 billion.
Bob Geldof hands back a scroll recording his Freedom of the City of Dublin to council officials in protest at the fact the honour is also held by Myanmar de facto leader Aung San Suu Kyi, whose country is accused of perpetrating ethnic cleansing against its minority Muslim Rohingya population. The move prompts support from U2 and in December the council votes to remove the honour from Suu Kyi.
Ireland's hopes of qualifying for the World Cup finals are dashed by Denmark. Meanwhile, in rugby, Ireland's bid to host its world cup fails to attract the required support and falters.
Sinn Féin president Gerry Adams announces his intention to step down as party leader after 34 years. Mary Lou McDonald becomes favourite to succeed him.
Engulfed by a political storm, Tánaiste Frances Fitzgerald finally resigns, averting a snap general election. Her resignation had been sought by Fianna Fáil following revelations of emails that showed she had been alerted to an aggressive Garda legal strategy aimed at whistleblower Sgt Maurice McCabe.
In its first finding, the Charleton Tribunal dismisses allegations of serious misconduct against gardaí and staff at the child and family agency Tusla made by Garda whistleblower Keith Harrison and his partner Marissa Simms. In a damning report, Mr Justice Peter Charleton says their allegations were without foundation and damaging.
The UK and European Commission reach a deal on Northern Ireland which assuages concerns raised by the Democratic Unionist Party (DUP). Observers say it sets the tone for a softer Brexit than had been initially envisaged. A clarification that Northern Ireland will not be isolated in the Brexit process may help to keep Britain closer to the EU; however, doubts linger.
Ryanair pilots ballot for industrial action, raising the prospect of passenger disruption over the busy Christmas period.
The highly anticipated Luas Cross City line opens in the capital but quickly helps aggravate traffic problems.
The Oireachtas Committee on the Eighth Amendment proposes repealing article 40.3.3 of the Constitution and allowing the Oireachtas to legislate. Pressure increases on the Government to hold a referendum.