Samantha Cameron must work out. Britain’s first lady was photographed in a floral bikini on Thursday while on a 10-day holiday there with her family. Luckily, David Cameron kept his shirt on.

Since her husband assumed office, Samantha Cameron has become a fashion force, and an active champion of the British fashion industry. She doesn’t have the selling power of Kate Middleton or Michelle Obama, but Cameron is an under-the-radar champion of homegrown talent, holding an active position as ambassador of the British Fashion Council and frequently wearing designs by British designers Roksanda Ilincic, Jonathan Saunders, and Peter Pilotto.

“She wears young, new designers in a palatable way and makes them look like wearable clothes,” Catherine Ostler, a contributing editor at The Daily Mail, told me of Cameron’s style following her official US visit last spring. And Melanie Rickey, fashion editor at large of the UK’s Grazia magazine said: “In Britain, there’s a big difference between being cool and being chic. Cool used to be the thing you wanted to be, but now it’s all about being chic. And [Samantha Cameron] is very, very chic.”