Yet the two have more in common than one might think. Guetta is a music-marketing mastermind who has forged innovative partnerships with brands like Renault, TAG Heuer, Beats by Dr. Dre, and MUMM Champagne, with whom he created the world’s first ‘double screen’ music video (the video plays on a computer and a mobile screen seamlessly). Guetta is also the most-followed DJ on social media in the world–he has over 55 million Facebook fans.

Guetta told the packed crowd that brands use celebrities in what he called an ‘old model’, essentially slapping a celebrity endorsement on a product, and expecting it to sell. Instead, he said celebrities must authentically believe in what they are endorsing and provide creative input into the campaign. “I don’t want to do something just for the money, something I don’t believe in… What I want is to achieve things that I could not without a brand. …if we do clever co-branding, we can all expand as brands,” he said. This is very similar to the advice Pharrell Williams delivered to the Cannes audience earlier in the week: “If you do things for money, they will know and they will turn their backs on you in two seconds. Make sure the main ingredient in everything you do is that your intentions are pure.”

The message is clear: for a brand-celebrity alliance to really sing, and cross influence each other’s “fans”, three song tips: honesty, “make each other better” and bring the (collective) fans an experience they want delivered by the brand-celeb duo that makes sense.