Contestants Of Beauty Pageant, Miss Universe 2011, São Paulo, Brazil

There are continually efforts to expand the pageant, but the participation of some countries such as Algeria has proven difficult due to cultural barriers to the swimsuit competition, while others such as Azerbaijan, Mozambique, Armenia and Nepal have balked at sending representatives due to the cost (in fact, of all the major international pageants, the franchise fee for Miss Universe is the most expensive). As of 2010, only four countries have been present at every Miss Universe since its inception in 1952: Canada, France, Germany, and the United States. Many European countries allow 17-year-old contestants to compete in their pageants, while Miss Universe's minimum age is 18, so national titleholders often have to be replaced by their runners-up. Miss Universe also prohibits transsexual applicants and age fabrication.
The main Miss Universe Pageant, as of now, is held over a two week period in May and July. In the 1970s through the 1990s, the pageant was a month long. This allowed time for rehearsals, appearances, and the preliminary competition, with the winner being crowned by the previous year's titleholder during the final competition.