In March 2006, Dreyfus successfully challenged the sitting Labor member for Isaacs, Ann Corcoran, for the right to contest the 2007 election.
 At the 2007 election, he defeated the Liberal candidate, Ross Fox, gaining a 5.9-point swing to Labor.

Following Labor's victory at the 2007 federal election, Dreyfus was appointed the chairman of the House of Representatives Legal and Constitutional Affairs Committee.
At the 2010 election, Dreyfus was re-elected, gaining a further 3.33-point swing to Labor.

In September 2010, Dreyfus was appointed as Cabinet Secretary as well as Parliamentary Secretary for Climate Change and Energy Efficiency in the Second Gillard Ministry.
Dreyfus took on additional responsibilities in December 2011 when he was appointed as Parliamentary Secretary for Industry and Innovation.
In March 2006, Dreyfus successfully challenged the sitting Labor member for Isaacs, Ann Corcoran, for the right to contest the 2007 election.  At the 2007 election, he defeated the Liberal candidate, Ross Fox, gaining a 5.9-point swing to Labor.
Following Labor's victory at the 2007 federal election, Dreyfus was appointed the chairman of the House of Representatives Legal and Constitutional Affairs Committee. At the 2010 election, Dreyfus was re-elected, gaining a further 3.33-point swing to Labor.
In September 2010, Dreyfus was appointed as Cabinet Secretary as well as Parliamentary Secretary for Climate Change and Energy Efficiency in the Second Gillard Ministry. Dreyfus took on additional responsibilities in December 2011 when he was appointed as Parliamentary Secretary for Industry and Innovation.
Mark Dreyfus