Browne contested the parliamentary seat of Argyll and Bute at the 1992 general election, and finished in fourth place behind the sitting Liberal Democrat MP Ray Michie.

Browne was selected to contest the safe Labour seat of Kilmarnock and Loudoun following the retirement of the sitting MP William McKelvey.

After Dewar left the Cabinet in 1999, to seek election as the First Minister of Scotland, Browne remained in post as PPS to the new Secretary of State John Reid.

[1] After the 2001 general election Browne entered Tony Blair's government as the Parliamentary Under Secretary of State at the Northern Ireland Office.

[7] Browne is vice chairman of the Washington, DC–based Nuclear Threat Initiative, a non-profit, nonpartisan organisation founded in 2001 by former U.S.

NTI's mission is to strengthen global security by reducing the risk of use and preventing the spread of nuclear, biological and chemical weapons.

[8] and he is also convenor of the Top Level Group of UK Parliamentarians for Multilateral Nuclear Disarmament and Non-proliferation, established in October 2009.