Starwood is one of the world's largest hotel and leisure companies. The company's service ranges from exclusive hotels such as the St. Regis and the Luxury Collection, key five-star hotels Sheraton and Westin, down to the moderately priced Four Points hotel chain of approximately Starwood is represented in most major markets around the world. The company operates a customer loyalty program called Starwood Preferred Guest (SPG), which allows customers to accumulate points for staying and with Starwood. The program is what unique in the industry in that its points never expire and that Starwood does not have so-called black-out dates (i.e., d when customers cannot use their points for redemption)