She was previously leader of the Progressive Democrats between 1993–2006 and from 2007–08. She resumed her role as leader in 2007 after her successor Michael McDowell lost his seat in the 2007 general election. She is the longest ever serving female member of Dáil Éireann.
During her time at university she made history by becoming the first female auditor of the College Historical Society. In 1976 she graduated with a Bachelor of Arts in Modern Studies and for a brief time was a secondary school teacher at Castleknock College in Dublin.
In November 2001 Harney married Brian Geoghegan, a business leader, in a low-key afternoon ceremony in Dublin on a day in which she attended to a number of other significant political meetings.
In 1979 Harney had her first electoral success when she was elected to Dublin County Council. Two years later she was successfully elected to the Dáil in the 1981 general election for Dublin South West. She has retained her seat at every election since then. Like many others in Fianna Fáil, Harney faced a number of problems from party leader Charles Haughey. As a leading member of the so-called Gang of 22, she was expelled from the party after voting in favour of the Anglo-Irish Agreement in 1985.
In 1989 the Progressive Democrats entered into a coalition government with Haughey's Fianna Fáil party. Harney was appointed Minister of State with responsibility for Environmental Protection. As Minister of State she legislated to ban the sale of bituminous coal in Dublin, thus eliminating the city's infamous smog.
She served in this position until the party withdrew from government in late 1992. In February 1993 Harney was appointed deputy-leader of the Progressive Democrats and succeeded O'Malley as party leader in October of that year.
Following the 2002 general election Harney led the Progressive Democrats, who had doubled their seats from four to eight, back into coalition with Fianna Fáil, the first time a government had been re-elected since 1969. She was re-appointed Tánaiste and Minister for Enterprise, Trade & Employment but was reported in 2003 as seeking a change. In a government reshuffle on 29 September 2004, she was appointed Minister for Health & Children.
Harney was Ireland's representative to the European Council of Ministers for the Software Patents Directive. Since the Council's first reading fell during the Irish Presidency of the European Council, she was chair of the meeting that discarded the amendments by the European Parliament which confirmed the exclusion of software innovations from what constitutes patentable subject matter.
In December 2001, Harney used a Government plane which was 50% funded by the European Commission to travel to County Leitrim to open a friend's off-licence in Manorhamilton. Harney later apologised for having abused her position in using the plane for non government business and admitted that using the plane was wrong. The aircraft was to be used 90% of the time exclusively for maritime surveillance.
In May 2006, the Irish Nurses Organisation unanimously passed a motion of no confidence in Mary Harney, accusing her of being negative and antagonistic towards nurses. Her policy of transferring private beds in public hospitals to privately operated hospitals has also attracted criticism.
In March 2006, 16 months after she took office as health minister, the INO claimed that a record number of 455 people were waiting on hospital trolleys on one day (although the Health Service Executive gave a figure of 363 people waiting on hospital trolleys for the same day). In June 2006, the Health Consumer Powerhouse ranked the Irish health service as the second least "consumer-friendly" in the European Union and Switzerland, coming 25th out of 26 countries, ahead of only Lithuania. However in the same survey conducted a year later, the Irish health service showed significant improvement, coming 16th out of 29 countries. Ireland even scored higher than Britain's NHS which came 17th in the survey.
In July 2006, Ireland on Sunday reported that Mary Harney's mother, Mrs Sarah Harney, jumped a queue of two emergency cases to receive hip surgery at The Adelaide and Meath Hospital in Tallaght. The allegation was strongly denied by the minister. 60% of respondents to an Irish Times/TNS mrbi poll in December 2006 said that the appointment of Ms. Harney to the position of Minister for Health had not led to any improvement in the health service. Fine Gael, Labour and Ms. Harney's own PD supporters were those who expressed most satisfaction with people in Dublin also feeling most dissatisfaction regionally. Harney rejected criticisms from Fine Gael during the same month that there had been a 25% increase in people waiting on trolleys in regional hospitals during the past two years; she claimed Health Service Executive statistics showed otherwise.
In 2006, in her capacity as Minister for Health, Mary Harney introduced risk equalisation into the Irish healthcare market. This was hugely resisted by Bupa. However, despite High Court proceedings, the controversial law was upheld. This has forced Bupa out of the Irish healthcare market (Bupa Ireland has since been bought by the Irish owned Quinn Group, averting any fear of redundancies). In January 2007, a leaked memo said that the planned Cancer Care Strategy, due for completion in 2011, would not be delivered on time. Harney denied this and said that since the leaking of the memo there had been much progress, although she did not elaborate. The plan was to allow for nationwide radiotherapy services by 2011.
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