Isobel Mary Redmond (born 8 April 1953) is an Australian former politician who served as the leader of the Opposition in South Australia and the leader of the South Australian Liberal Party from 2009 and 2013. She was the member of parliament (MP) for the electorate of Heysen from 2002 to 2018.

Redmond was born in Engadine and raised in Heathcote, completing her education in 1971. Redmond funded her education on her own while she worked as a clerk in the Crown Solicitor's Office and pursued law studies part time by taking night classes. After traveling around Australia and getting involved with the Australian Labor Party for some time, she relocated to Adelaide Hills in 1978 along with her husband. As a solicitor, she ran her own firm and opened up a private practice in Stirling after winning the lottery in the early 1990s. She had legal practice with regards to native title cases for the Mirning people. Redmond was also active in local councils, including serving as the president of the Rotary Club of Stirling.

In 2002, Redmond won a seat in the South Australian House of Assembly as the Liberal MP for Heysen by taking a majority vote after preferences were distributed and thereby succeeded David Wotton. In 2004, she joined Rob Kerin's shadow cabinet as shadow minister of Housing, Families and Communities, Ageing and Disability. In her capacity as shadow minister for these departments, she actively took part in formulating opposition policy on and participating in debate regarding disability services, care standards and heritage related issues. Following the electoral loss by the Liberal Party in 2006, she occupied important positions in the shadow ministry under both Iain Evans and Martin Hamilton-Smith as shadow Attorney-General and Shadow Minister for Justice, Arts and subsequently for Road Safety. As such, she participated in debates on law reform, rights of victims, criminal law and professional conduct in the legal sector. She also had a hand in debates on internal party leadership as well as introducing Independent Commission Against Corruption (ICAC) reform measures and heritage protection legislation.

Redmond served as Leader of the South Australian Liberal Party from July 2009 to January 2013, following a party-room ballot in which she defeated Vickie Chapman. As leader, she led the Liberal Party at the 2010 South Australian state election and continued in the role of Opposition Leader following the election outcome. During her leadership, she held positions on issues including anti-corruption reform, public sector administration, infrastructure policy, and parliamentary procedures, and was involved in negotiations and debate surrounding the establishment of a state ICAC. She remained leader following an internal leadership challenge in 2012 but resigned in January 2013 due to ongoing internal party tensions, and continued as the member for Heysen until her retirement from parliament at the 2018 state election.

Redmond was born on 8 April 1953 in Engadine and grew up in Heathcote near Wollongong. She attended Heathcote High School, completing her secondary education in 1971. Redmond attended public schools and funded her own university studies, later becoming the first member of her family to attend university. In her youth, she owned a terrace house in Newtown, which was later purchased by Frank Sartor. At the age of 18 or 19, she travelled across Australia on a three-week bus trip and visited the Adelaide Hills for the first time, later deciding she wanted to live there. While studying law through night classes with the New South Wales Barristers Admission Board, she worked as a clerk in the Crown Solicitor's Office. In her twenties, Redmond briefly joined the Australian Labor Party but left after attending one meeting.

After relocating to the Adelaide Hills with her husband in 1978, Redmond established a legal practice and later opened her own office in Stirling in the early 1990s after winning A$25,000 on a scratch lottery ticket received from her parents at Christmas. During her legal career, she became involved in a native title claim for the Mirning people despite having no prior experience in the field. The work involved extensive travel across the Nullarbor Plain and engagement with Indigenous communities over several years. Redmond became involved in politics through local government and community advocacy in the Adelaide Hills. During the 1980s, she campaigned against redevelopment proposals for the main street of Aldgate. She served on the Stirling District Council from 1982 to 1987 and later worked as a self-employed solicitor for six years before entering parliament. Simultaneously, she was also the president of the Rotary Club of Stirling from 1999 to 2000.

Redmond was elected to the parliament of South Australia on 9 February 2002 to the seat of Heysen for the South Australian Liberal Party. Redmond obtained 8,042 votes in the primary voting, which marked a swing of -3.8%, giving her 8,699 votes after the allocation of preferences, or 55.7% of the two-party-preferred vote. She succeeded David Wotton following his retirement.

Redmond was appointed as Shadow Minister for Housing and Shadow Minister for Families and Communities in the shadow cabinet of Rob Kerin. This was on 1 April 2004. She also took up the portfolios of Shadow Minister for Ageing and Shadow Minister for Disability on 18 April. On 12 July, Redmond called for an independent inquiry headed by a retired judge or Queen's Counsel concerning a matter at the Strathmont Centre due to concerns over oversight and professional standards within disability care facilities. At the same time, she supported the proposed sale of Beechwood Garden in Stirling but argued for protection of the building's heritage value through legislation. On 18 September, following the Vini Ciccarello affair, Redmond said that improper behavior within the parliament would be taken seriously regardless of the gender of the person involved.