She is charged with strengthening the office's authority across Whitehall and helping the Government meet its self-imposed targets on spending efficiency.
In the newly created position, Hastings reports to chief executive John Oughton and oversees a team of 16.
Her primary audience is other government departments, but she also has a brief to communicate to the public that the Government is committed to efficiency savings, she told PRWeek.
‘My challenge will be to help the departments understand the help and advice that comes from the Office of Government Commerce. It is always difficult because people want to manage their own finances,' Hastings said.
She is a former head of corporate communications strategy at the BBC.
The Office of Government Commerce is charged with sharing best practice, particularly where multiple departments combine to spend money on projects.
The OGC - an office of the Treasury - is responsible for supporting the implementation of the Lyons Review, which recommended the relocation of part of the civil service.
The office is aiming to achieve £21.5bn in savings by 2007 - most of that figure coming from improved procurement procedures.
The OGC also helps the public sector apply European procurement rules.
Before the Department for Constitutional Affairs, Hastings was director of comms at London Business School.