The Turks and Caicos Islands, a British commonwealth of roughly 30 islands in the Caribbean, occupy a small piece of paradise. The isle of Dellis Cay, for instance, is a sanctuary for local sea birds that live there year-round and an important stopover for migratory birds that fly across its miles of sandy beaches. But the flamingos and herons are getting some human neighbors in a development dubbed The O Property Collection: pricey residences by a flock of big-name architects including Shigeru Ban, Kengo Kuma, and Zaha Hadid. For many observers, the project raises troubling questions about sustainability.

Created by the Turkish businessman Cem Kinay, the development features 124 private villas, 154 residences, a Mandarin Oriental hotel, and a marina located on a 35-acre beachfront site. Residences will range from $2 million to $20 million and are aimed at those looking to purchase their third and fourth houses. The development broke ground in January and is slated for completion at the end of 2009.