Worth stepped down as the Prime Minister’s special adviser in June 2012 and had been prevented from directly lobbying the Government for most of his time at MHP. However, the restriction, imposed by the Advisory Committee on Business Appointments, expired in June.
His hire, described as a "coup" by one public affairs figure, strengthens the agency's government ties. Quiller, which does not give its staff job titles, already includes former Conservative campaign director George Bridges among its ranks.
After leaving Number 10, Worth wrote a paper for Policy Exchange calling for greater involvement of the private sector in the provision of public services.
Worth told PRWeek his remit at Quiller would be wide-ranging, with the 2015 general election opening up opportunities.
"There is a very important election coming up," he said, "and there is quite a lot of confusion about what that means, for example in terms of how another coalition would work were it to be voted in. I think we’ll see the election fought around issues such as the economy, consumer issues and of course public services, which has been an area of focus for me."