Forget rough-around-the-edges eco-outposts. Central America's latest wave of nature lodges is all about creature comforts. Alison Humes happily wades in

Punta Caracol Acqua Lodge, on Isla Colón in Panama's Bocas del Toro archipelago, curls like a shell suspended over the sea. Here are the pure essences of Caribbean beauty—ocean, breeze, wood and thatch, and not much more. Six cabanas rest on stilts over the water, spaced like vertebrae along a spine of boardwalk. The deck leads to a large open-air pavilion where guests gather for meals or linger over tea. Boats carrying new arrivals or fresh fish dock alongside. Everything is simple, elegant. The aesthetic is both spare and profoundly persuasive. In my carved-wood canopy bed, I hear only the sea lapping at the legs of my cabin. Sitting up, I look through the space under the eaves of the thatched-palm roof to gentle swells and a new world beyond.

The hotel has as its mission an attractive vision of living well but lightly on the earth. Each cabin has its own rooftop solar panel and hot-water heater. All sewage and wastewater are pumped to a biodigester onshore that converts them to methane and fertilizer. Even the soap in the bathroom is biodegradable.

Opened in 2001, Punta Caracol—called an "acqua lodge" because it literally stands in the water—is one in a new wave of resorts and hotels that signals a major evolution in Central American tourism. Beautiful, comfortable, and sensitive to the environment, these places are attracting a new kind of customer to the region: one with disposable income, multiple interests, and high expectations. My mission? To search out Central America's most progressive accommodations—here in the Bocas del Toro, as well as on the tip of Costa Rica's Nicoya Peninsula, next to a national park in Honduras, and along the coast of Belize. Each country has its own approach to integrating tourism and ecology, but all recognize the importance of doing so. Costa Rica, for one, has a groundbreaking ecocertification program for hotels and resorts; Honduras is carefully situating new hotels so as to capitalize on its magnificent Mayan site, Copán, and its world-class Caribbean beaches without overwhelming them. Plans like these have encouraged the current crop of imaginative entrepreneurs and will pave the way for even larger players.

Pilar, a slight, fine-boned woman from Barcelóna who wears tropical-pink lipstick, is one of Punta Caracol's proprietors. She wants her guests to experience the perfection of this place, to get away from what she calls "the stress," while she quietly works like a dervish to pull it all off. "Few schools around here train people to work in the tourist industry," she explains, smiling, apologizing for her constant motion. While managing reception, the books, the food, the cleaning, she is also instructing her small staff of fifteen. She sends me to explore the area with Joaquín, a young man in his thirties who wields his old speedboat like a hatchet, skimming and chopping into the swells. With me are Monica and Antoine, a couple on their honeymoon. Monica is in her twenties, a lawyer from Spain—sun-kissed, slim, and unselfconsciously chic. Her new husband is more shy, a Frenchman (from "a town called Limoges," he says, with a dismissive roll of the eyes) and a hydraulic engineer.