The designer who goes only by Clodagh is perhaps best known for the duplex she designed for Robert Redford, but she is also one of the world’s top spa designers (think Elizabeth Arden, Spa de Serville and Sasquana Spa). Here she offers her fantasy yacht spa.

“I picture a sauna and steam room with portholes under water, a glass box for the spa treatment room with a 260-degree ocean view and a glass floor for a look at the ocean denizens while you are lying face down. Long banquettes covered with fluffy, white, terry cloth for lounging after self-indulgent treatments, a ladder to the sea so that the cold plunge could be a real seawater plunge and an outdoor hot shower to ease the shivers when you come out. Hammocks slung under awnings where you can watch the waves. A thirty-foot lap pool with a retractable skylight roof...or maybe a hundred-foot lap pool, how mega are we? A deep tub for soaking in seaweed...a spray booth for a bronzed body from day one and a selection of chalk-white swimsuits to set it off. Champagne and black chocolate in the fridge with a few healthy snacks and a private juice bar. A shiatsu room with a floor mattress draped in Asian silks and cottons all in indigo and white. And I see a teak-lined meditation room tucked up on the back deck where the wind is quiet.”