Dame Margaret Georgina Constance Guilfoyle AC DBE (/ˈɡɪlfɔɪl/; née McCartney; 15 May 1926 – 11 November 2020) was an Australian politician who served as a senator for Victoria from 1971 to 1987, representing the Liberal Party.

She was the second of three children born to Elizabeth Jane (née Ellis) and William McCartney; her father worked as a civil servant and her mother was a schoolteacher before her marriage.

She was mentored by Elizabeth Couchman and Senator Ivy Wedgwood, who encouraged her to seek leadership positions within the party's organisational wing.

[1] As part of the latter, in December 1973 she joined Ellis Lawrie and Bob Cotton in submitting a minority report that advocated the abolition of inheritance tax; their recommendations were eventually adopted almost a decade later.

The Herald described her as "a housewife with a big say on prices",[1] while The Sunday Telegraph reported that she would be "looked upon by Australian housewives as their special friend in Canberra".

[10] She strongly resisted pressure to cut her department's budget, arguing that regular increases were needed simply to maintain existing programs.

[1] She had an often tense relationship with Treasurer Phillip Lynch, who complained to Fraser that she was the most uncooperative minister in identifying potential spending cuts.

[11] During her tenure, Guilfoyle oversaw a major reform of the national child endowment scheme, introducing direct cash payments rather than tax rebates.

[b] Working with Marie Coleman as the office's director, she oversaw a major expansion of the federal government's activities in the childcare sector, introducing or expanding funding for preschool, daycare, after-school care, and youth refuges.

[1] She was a key member of the Review of Commonwealth Functions Committee, a cabinet subcommittee nicknamed the "razor gang" that was tasked with cutting government expenditure.

She was made spokesperson for finance and taxation in Andrew Peacock's shadow ministry, but resigned the position after the 1984 election, and spent her remaining years in the Senate as a backbencher.

As well as her public-sector appointments, Guilfoyle also served on the boards of a number of non-profit organisations, including the Australian Children's Television Foundation, the Victorian State Opera, the Mental Health Research Institute and the Infertility Treatment Authority.

[16] On 13 June 2005, Guilfyle was appointed Companion of the Order of Australia (AC)[26] Guilfoyle remained involved with the Liberal Party after leaving parliament.

She had the support of Jeff Kennett and Andrew Peacock, but withdrew from the race in favour of Malcolm Fraser; the successful candidate was Tony Staley, another of her cabinet colleagues.

[20] In 1976, Mungo MacCallum published an article in the Nation Review magazine alleging that Guilfoyle was having an extramarital affair with Jim Killen, one of her cabinet colleagues.