Stringer's appointment is part of an upcoming drive by the trade body to deal with the numerous regulatory question marks surrounding the online sector.
With Brussels and the UK Government increasingly turning the spotlight on online regulation, the IAB is preparing a self-regulation framework for the sector.
Stringer previously led Orange's UK public affairs efforts and advised the company's senior management team on regulatory and legislative issues. He joined Orange as public affairs executive in 2001, having worked as a public affairs consultant.
In his new role, he will report to IAB chief executive Guy Phillipson, who labelled the appointment "an essential hire for the IAB".
Phillipson said Stringer would work with media owners, regulators and the Government to promote the importance of online advertising within the self-regulatory system.
He will lobby for the freedom to advertise online, as well as being the IAB's representative at the Advertising Association and liaising with organisations including the Advertising Standards Authority, the Committee of Advertising Practice and Ofcom.
While traditional media have been subject to stringent new regulations regarding issues such as junk food advertising, the internet has often been viewed by brands as a route to youth markets and a way around tough legislation.
Last month, however, a range of companies including Burger King, Coca-Cola, Mars, Nestle and Unilever signed the so-called EU Pledge that will see them phase out advertising many of their products to under 12-year-olds by the end of 2008.
The agreement covers all media and some firms have started pulling campaigns aimed at young people.
The pending Google takeover of DoubleClick is likely to intensify the scrutiny of online advertising, as the search engine seeks to add display advertising to its offering.
Stringer will also chair the IAB's new Regulatory Affairs Council.