Immersion suites—the ultimate amenity for well-being—are popping up at resorts across the globe. At the Guanahani (590/590-276-660; www.leguanahani.com; doubles from $820) on St. Bart's, the Wellness Suite comes with an ocean-view terrace and after-hours access to the adjacent Clarins spa pool. ● In the three Rejuvenating Spa Suites at Los Cabos, Mexico's Las Ventanas (888/767-3966; www.lasventanas.com; doubles from $2,300), your own spa butler will lead yoga sessions and whip up healthy elixirs. ● The Grand Hyatt Erawan Bangkok (800/633-7318; bangkok.grand.hyatt.com; doubles from $576) has six spa cottages— with Thai-massage beds and outdoor showers—designed by Tony Chi; they sit above the hotel in a rooftop garden. ● The Renewal Suite in the Westin Times Square (800/937-8461; www.westin.com; doubles from $1,500) helps soothe frazzled senses with a chromatherapy infinity tub and decompression chamber. No need to eat or drink outside your room: the mini-bar is stocked with organic wines and vitamin-infused gummy bears.