On 7 May 1986 Alston was appointed by the Parliament of Victoria under section 15 of the Australian Constitution to fill the vacancy in the Australian Senate caused by the death of Senator Alan Missen. He was re-elected in 1987, 1990, 1996 and 2001.^[1]

Alston was a member of the Opposition Shadow Ministry from 1989 to 1996, and was Deputy Leader of the Opposition in the Senate 1993–96. Shadow Minister for Social Security, Child Care and Superannuation, as well as Communications and the Arts, were among the positions he held in the shadow ministry. He was Minister for Communications and the Arts 1996–97, Minister for Communications, the Information Economy and the Arts 1997–98 and Minister for Communications, Information Technology and the Arts 1998–2003. He was also Deputy Leader of the Government in the Senate 1996–2003.

Alston resigned from the Senate on 10 February 2004,^[1] and he was replaced by Mitch Fifield.

After leaving Parliament he was actively involved in businesses both in Australia and abroad. For seven years he was a member of the international advisory board of CQS LLP, one of the world's largest hedge funds and later on the board of its Australian subsidiary. For six years he was a director of a UK public company Chime plc. From 2010 to 2013 he was a member of the Asia-Pacific advisory board of Alcatel-Lucent.

He has chaired the boards of three publicly listed Australian companies, as well as Sunny Ridge, Australia's largest strawberry farm. He has been a member of the national and Victorian boards of the Australia China Business Council. He has been a member of the advisory board of investor relations firm, Market Eye, chairman of Qato, an Australian long-short fund, a director of Nanuk Asset Management, a director of CPA Australia for three years. and a director for many years of Balmoral Gardens, a retirement village owner. He is currently a director of China Telecom (Australia), chairman of National Advisory, an Australian corporate advisory firm and a member of the Council of the National Gallery of Australia.

He has served as the chairman of the Alliance Circle, an advisory board to an international partnership between Monash University and Warwick University (UK). He has been chairman of the Docklands Community Centre project and a board member of Chaplains Without Borders. From 2009 to 2011 he was chairman of the Melba Foundation, the owner of Melba Recordings, producers of internationally renowned classical music. Since 2009 he has been an adjunct professor at Bond University and a member of the board of trustees. He is also an adjunct ssociate professor at the University of NSW, Canberra. He is an ambassador-at-large of RedR Australia.

Alston was educated at Xavier College (Kew), the University of Melbourne and Monash University, graduating with bachelor's degrees in law, arts and commerce from Melbourne University and master's degrees in law and business administration from Monash University. He was a barrister before entering politics.^{[citation needed]}

His brother is noted academic Philip Alston. From February 2005 to February 2008, Alston served as Australian High Commissioner to the United Kingdom. Since 2004 he has been an adjunct professor of information technology at Bond University. Since 2022 he has been an adjunct associate professor at the University of NSW, UNSW Canberra. c^[2]

Since leaving Parliament, Alston has served as chairman of three listed Australian companies and as a director of a number of listed public companies in both Australia and the United Kingdom. These have been in fields as diverse as information technology, broadcasting services, sandalwood, public relations, advertising and ironsands.^{[citation needed]}

Alston served as a member of the international board of CQS LLP,^[3][4] a United Kingdom-based hedge fund for seven years and as a director of its Australian subsidiary. Alston also served for six years as a director of United Kingdom-based public company, Chime PLC.^[5] He also served as chairman of the advisory board of Qato Capital,an Australian long short fund, as a director of Nanuk Asset Management and as a director of Balmoral Gardens, a retirement village owner and operator for many years and a director of CPA Australia for three years..

Alston was federal president of the Liberal Party from 2014 to 2017. ^[6]

• More to Life than Politics? (2020), a memoir
• Australia, the United States and China in a Post-Covid World (2020)
• Reflections on the EU Project and its Flaws: A Fatal Conceit about Markets and the Real World (2021)
• Donald Trump: The Ultimate Contrarian (2021)
• Their ABC: Inside Australia's Largest Sheltered Workshop (2022)
• "Freedom of speech and diversity of expression", in Dignity and Prosperity (2003)

At the 2015 Australia Day Honours, Alston was appointed an Officer of the Order of Australia for distinguished service to the Parliament of Australia, to international relations through diplomatic roles, to business development in diverse sectors, and to the community.^[7] Alston was also awarded the Centenary Medal in 2001 for service as Minister for Communications, Information Technology and the Arts.^[8]