Air travel historians will tell you that the concept of business-class travel emerged just 23 years ago. Before that, there were two ways to fly: first class or tourist class.

The consensus is that business debuted as a class unto itself when a forward thinker at Dutch carrier KLM decided to add a cabin section where business travelers, who were paying a premium for short-notice flights, could benefit from enhanced in-flight service. It was a great idea with a not-so-sexy name: KLM dubbed the new class of travel the Full Service Facilities Zone, or FSFZ for short. Australia’s Qantas followed suit, but named its enhanced-service cabin Business Class.

Many moons later, TWA launched an upgraded economy-class cabin system-wide in an effort to entice business travelers back into the fold. Since extra legroom was a key feature of the new configuration, TWA capitalized on that aspect with an advertising campaign featuring the long-legged beauties of the Radio City Rockettes seated in the cabin, crossing and recrossing their legendary gams.

If, as the saying goes, imitation is the sincerest form of flattery, TWA must have been truly honored when other carriers eventually followed suit. For example, American Airlines launched a “more room in coach” promotion, which met with rave reviews when it debuted. (Unfortunately, post-9/11 cuts forced American to eliminate the extra legroom on most of its aircraft.) United Airlines added its premium economy class shortly after American, and remains the only U.S. carrier to offer a distinct and separate third and fourth class of service on select routes.

United has taken an interesting approach to taking care of its top flyers. Advance seating assignment in Economy Plus is available on a first-come, firstserve basis to the following customers: Mileage Plus members with Premier status or above, Star Alliance Gold and Silver members, and passengers traveling on fares booked in Y, B or M class. Additionally, in some markets you can secure an upgrade to Economy Plus, based on availability, at a selfserve kiosk for a small fee, usually less than $30.

United passengers willing to pay a premium for better service on trans-continental flights can book seats in the relatively new p.s. (for “premium service”) cabin. Offered on flights connecting New York (JFK) and Los Angeles (LAX), and New York and San Francisco (SFO), United’s p.s. cabin features the only lie-flat seat available on domestic flights.

EVA Airways introduced its premium economy, called Evergreen Deluxe, in 1992 for its first flights to the United States. Seat-back entertainment systems in the Evergreen Deluxe cabin feature two news channels, several music channels and an assortment of movies. EVA is dedicated to serving its premium-economy-class passengers and it shows: passengers cite it as a wonderful alternative for business travelers on a budget.

Virgin Atlantic started with the two-class configuration and added premium economy. Virgin’s business class, one of the best in the industry, commands a higher fare, so many passengers opt for the more budgetfriendly premium economy class.

Singapore Airlines recently launched nonstop service from New York (EWR) to Singapore (SIN) and Los Angeles (LAX) aboard aircraft that offer only premium economy class. Dubbed Executive Economy, it boasts the industry’s largest economy-class seats, larger-than-the-norm personal video monitors and many luxuries — such as in-flight lounges and snack bars — not offered even in some carriers’ business-class cabins. Singapore’s goal, which it appears to have achieved, was to make the 18-hour flight as comfortable as possible.

“The world’s longest flight called for the creation of the world’s most spacious and luxurious economy class,” said Kenneth Bright, Singapore Airlines vice president of marketing/USA. “Four hundred on-demand entertainment options at every seat; adaptor-free in-seat power for laptops; and dedicated self-serve snack an d lounge areas are among the many features that have made Singapore Airlines’ new Executive Economy class a favorite among ultra-long-haul travelers.”

While BMI offers business- and economy-class service on its European routes, the British carrier operates three-class service — business, premium economy and economy — on its long-haul routes.

“BMI’s premium economy offers travelers extra individual service with dedicated onboard flight attendants for that cabin, upgraded amenities and a more comfortable ride due to enhanced seat pitch,” said Denise Harvill, BMI’s director of international sales/marketing USA. “We also have consistently made our pricing attractive for our business and leisure customers alike.”

British Airways’ World Traveller Plus is another excellent alternative to business class for travelers on a budget. In fact, BA makes it easy to mix and match services, allowing passengers from North America to book business class to London to take advantage of the lie-flat bed and arrive at their destination ready to work, and book World Traveller Plus for the return, when getting a period of solid rest is not a priority. BA’s World Traveller Plus includes choice of in-flight meal, individual video monitors and even a small amenity kit.

A quick review of the chart accompanying this article begs the question: is premium economy today’s business class?