Integrate, respect and amuse
Allowing an advertiser to communicate about their brand, its values is far more complex than simply communicating about products. For the magic to work, you need several ingredients: a perfect integration with the publisher's website, advertising is part of the browsing experience and must not distort the latter. It must also respect the user, who probably did not arrive on the site to view advertisements. Finally, for acceptance to be complete it is necessary that advertising be fun, beautiful and rewarding also for the reader.