The main issues which caused the Coalition partners to fall out include the following.
Five months after the October 1997 election it emerged the then minister for foreign affairs, Mr Ray Burke, had been involved in a passports scandal. The Taoiseach, Mr Ahern, had made three inquiries into the issue before forming the Government but did not tell the Tanaiste this. In June Ms Harney said the PDs would not have gone into government had they had known about financial contributions to Mr Burke.
In November 1998 the Minister of State for Foreign Affairs, Ms Liz O'Donnell, laid down a marker that she was not shy of upsetting the coalition partnership. Unhappy at budget allocations for overseas aid, said she would resign unless it was increased.
Allegations were made that the then EU Commissioner, Mr Padraig Flynn, had received donations from property developer Mr Tom Gilmartin. Mr Ahern admitted he had been wrong about how often he met Mr Gilmartin. Ms Harney said the events "strained the relationship".
In March 1999 architect Philip Sheedy's release from jail was followed by the controversial resignation of two judges. Ms Harney said she was "unhappy" with the Taoiseach's initial refusal to inform the Dail of his role in the controversy.
In November that year it emerged that Mr John Ellis, Fianna Fail TD for Sligo/Leitrim and then chairman of the Dail Committee on Agriculture and the Marine, had had debts written off by National Irish Bank while owing farmers £300,000 after his meat business collapsed in the late 1980s.
While Mr Ahern said the events were "really consigned to history", Ms Liz O'Donnell said he should consider his position. Mr Ellis eventually resigned from the committee. Months later FF TD Mr Denis Foley resigned from the Dail Committee of Public Accounts after it emerged he held Ansbacher accounts.
Ms Liz O'Donnell criticised the Minister for Justice, Mr O'Donoghue, over the treatment of asylum-seekers which she described as a "shambles". The Minister responded by saying he would "not be deflected in my efforts to deal with the issue". Ms Harney said it was unacceptable for people to wait five years for a decision on their asylum application.
In July 2000 it was Ms Harney's turn to cause problems for the Coalition when a judge ruled that her comments in a newspaper article had posed a risk to a fair trial for Mr Charles Haughey, facing charges of obstructing the McCracken tribunal. She offered her resignation but Mr Ahern refused it.
Pigs on family farm of the then minister of state for agriculture, Mr Ned O'Keeffe, were found to be fed with bonemeal, linked to the spread of BSE. Ms Liz O'Donnell refused to support the Government and abstained on a vote on a private member's motion critical of the minister last December. Mr O'Keeffe resigned his ministerial post in February.