The three-day conference in the Scottish city brings together some 450 participants from 60-odd countries to tackle issues from the rise of the Internet and citizen journalism to the future of public service broadcasting.
"We are expecting politicians and diplomats of world fame to participate, along with journalists and even the occasional celebrity -- where they have something to say," said IPI vice chairman Mark Damazer.
Founded in the United States in 1950 and based in Vienna, the IPI is a network of editors, media executives and leading journalists from some 120 countries dedicated to press freedom and improving journalism practices.
In Edinburgh, South African Deputy President Phumzile Mlambo-Ngcuka will make a keynote speech on Africa, a year on from the last IPI congress in Nairobi.
The special session will look at what happened to the Africa story since the high-profile Live8 concerts last year.
"There will be sessions on topics that have animated passions for much of