Mardi Stewart is currently employed by the Department of Immigration and Citizenship (DIAC) as director of internal and strategic communications where she is responsible for the development and implementation of communication activities for the 8,000 DIAC staff located in 80 locations around the globe.

Mardi's experience has spanned the public, private and not-for-profit sectors. Following University she worked as a liaison officer for the Deputy Prime Minister, The Hon. Brian Howe. Mardi has also held the position of manager of public affairs at the Sydney Children's Hospital where her contribution significantly increased the profile of the hospital; through the management of communications for the $230M redevelopment of the hospital, and the organisation of high profile special visits for sick children by Her Majesty Queen Elizabeth II , Michael Jackson, the Manchester United Football Team, The Corrs and Savage Garden.

In 2000 Mardi founded her own communications consultancy and for the next 10 years provided communications and media related services to over 20 long term business clients.

Mardi is the recipient of the Public Relations Institute of Australia (PRIA) 2009 Golden Target Award for the best community relations campaign, and the 2000 NSW Central Coast Young Businesswoman of the Year Award.