While there, she became heavily involved in both student politics and community organisations, becoming the ACT Co-ordinator of the Young Women's Electoral Lobby in 1998.

In the same year, she was also secretary of the university student body, a member of the party executive in the ACT, and the founding co-convenor of the Vida Women's Network – an attempt to form a Democrat version of EMILY's List Australia.

[3] In September 2000 she unsuccessfully ran for President of the Australian National University Students' Association, as the leader of a combined Democrat/Liberal election ticket.

Dundas worked as an organiser for the Community and Public Sector Union for several months in 2001, before gaining the top position on the Democrat ticket for the seat of Ginninderra in the ACT Legislative Assembly.

Roslyn Dundas stood in the left wing of the party, along with the likes of Senators Natasha Stott Despoja and Brian Greig.