Waterfall will wind down his day-to-day responsibilities as a creative director on specific accounts over the coming months. He plans to take some time off before working out his plans.
The Poke co-founders Iain Tait and Nicolas Roope will now work as joint creative directors across the agency's portfolio of clients.
Waterfall said: "Poke will always be an amazing place to challenge yourself. It's a company that, at its heart, has an internal desire to 'make it better', think in new ways and push every brief and expectation."
He added: "Now is the time for me personally to challenge myself again, use some of my different skills from the range of creative disciplines and make myself sweat a bit. I don't know what or where, but I know I have the energy to carry on Poke's attitude to different arenas."