Iain Aitken Stewart CBE (born 18 September 1972) is a British Conservative Party politician and former accountant.

[2] Stewart stood unsuccessfully as the Conservative Party candidate in the 1999 Scottish Parliament election, for the Glasgow Rutherglen constituency, finishing fourth.

He successfully stood against Starkey for the redrawn Milton Keynes South constituency in the 2010 general election, winning by 5,201 votes.

Stewart responded that there was no conflict of interest in renting from his staff member as the flat is let "on a proper legal contract" and fully approved by the expenses watchdog.

and chair of the Transport Committee, claimed £51,896 on hotels in London, despite living in a constituency just 35 minutes' train ride from the capital.

In June 2017, Stewart was returned as the MP for Milton Keynes South with a majority of 1,725 over Labour candidate Hannah O'Neill.

[9] In December 2017, following the publication of the National Infrastructure Commission's report on the Oxford-Milton Keynes-Cambridge corridor, he was appointed as the Government's official champion for the project.

Stewart is openly gay and was formerly Deputy chairman (Political) of LGBTory, the Conservative LGBTQ Group.