(FORTUNE Magazine) – ''This is the generation of American architects,'' proclaims Philip Johnson, at 80 the nation's foremost master builder. Now in their 30s and 40s, all have made their names young in a field where traditions of long apprenticeship favor the old. Some reinterpret history, often echoing the golden era of the 1930s skyscraper. Others create structures that vibrate with bold geometric shapes and brash colors. Still others strive to combine futuristic flair with historical detail. Whatever their style, these men and women make beautiful buildings that are also sound investments commanding steep rentals and high resale prices. Says developer William Zeckendorf Jr.: ''You can't put a dollar sign on it, but having a well-known architect design your building has everything to do with getting through the approval process, attracting tenants, and satisfying your own desires.'' Here are seven top American architects. As shapers of urban horizons, they are influential and affluent but rarely super-rich. Although their fees often run 4% to 6% of construction costs, profits are consumed by armies of draftsmen and engineers needed for the many design details.

BERNARDO FORT-BRESCIA AND LAURINDA SPEAR: THE ICONOCLASTS In his stark, white conference room atop a sleek Miami office building, Bernardo Fort-Brescia explains where he fits into the scheme of modern architecture. ''If the traditional architects like Robert Stern -- the ones who love history -- are here,'' he says, giving the white table top a soft karate chop, ''and the neomodernists like Helmut Jahn are here,'' he gives another chop a few inches to the left, ''then I'm here,'' he adds, extending his arm as far as he can toward a floor-to-ceiling window about five feet away. Fort-Brescia and his wife, Laurinda Spear, both 35, run Arquitectonica -- the word is Spanish for architectural -- a young Miami firm whose futuristic designs startle the eye with their imaginative use of colors and architectural stunts. Some of Arquitectonica's high-rise condominiums, houses, and office buildings dotting the Miami waterfront are said to have inspired Miami Vice's hip tropical colors and horizontal lines. In 1980 Fort-Brescia and Spear designed the Atlantis, a Miami condominium project that cost $14 million to construct. It jarred architectural sensibilities and brought the pair national recognition. It is a 20-story slab shaped like a submarine's conning tower, with a curved facade on one side whose windows provide a spectacular view of Biscayne Bay. To give it a surreal touch, Fort-Brescia and Spear placed a giant red triangular prism on the roof and punched out a 37-foot cube from the building's middle. This hole, known as the skycourt, sits 12 stories up and has become a pleasurable hangout for tenants, with its whirlpool, red spiral staircase, and palm tree. The skycourt also allowed the developer, Parkview Group, to take advantage of Miami's zoning laws and build extra apartments on the roof with better views -- and higher prices.

When most of his classmates from Harvard's Graduate School of Design headed for New York and Chicago in the mid-1970s, Fort-Brescia moved to Florida to teach at the University of Miami. There he worked with Laurinda Spear, who had just graduated from Columbia's School of Architecture and Planning, to design her parents' waterfront house. This shocking-pink stucco structure, known as the Pink House, became one of the most widely photographed homes in America. It has appeared in advertisements for Money magazine. Despite the well-founded belief that there's nothing like home construction to ruin a relationship, the two were married in the middle of the job. In 1979 Fort-Brescia got his big break in corporate architecture when at the age of 28 he won a commission to design a 42-story Miami condominium costing roughly $30 million for New York developer Harry Helmsley. Fort-Brescia had heard about the project from his family of prominent Peruvian businessmen and ! called Helmsley's New York office to solicit the job. When he was denied an interview on the ground that Helmsley wanted an established architect, Fort- Brescia flew to New York and left a message at Helmsley's office to call and cancel if he couldn't meet him the following morning. The ruse worked. Helmsley called back to confirm, and when the two men met, Fort-Brescia made his pitch and got the job. Today Fort-Brescia and Spear run the Miami office and branches in Chicago and New York, where they oversee 45 architects. Though both design, Fort- Brescia does most of the traveling and the selling, while Spear stays in Miami close to the drafting table and their three children. Current projects include a courthouse for Dade County, Florida, an $88-million shopping center in Fort Lauderdale, and a $170-million apartment complex in San Francisco. In the last stages of completion is a 530,000-square-foot headquarters for Banco de Credito del Peru, in Lima, which is sheathed in black marble and constructed around the remains of an Inca ruin. As Fort-Brescia explains, in his Spanish accent: ''I look at my work as an attitude, not a style. I'm always experimenting, looking at new ways of doing things and at better ways of doing things.''

DAVID CHILDS: THE CLASSICIST The IBM of architecture is Skidmore Owings & Merrill -- huge, professional, profitable. When you hire David Childs, the chief designer of the firm's New York City office, you get not only his considerable design expertise but also a supermanager who oversees SOM's massive backup staff, which takes care of every drafting and engineering problem imaginable. Building a major high-rise is a vastly complicated manufacturing and logistical process. A typical skyscraper might contain 5,000 windows, 7,500 doorknobs, and 60 miles of electrical wiring. At the peak of construction, as many as 10,000 people can be involved. The process requires the mind of a field marshal and the eye of an artist. Childs, 46, came from a family of physicians and was on his way to being a surgeon when he realized that his true desire was to draw buildings, not blood. He enrolled in Yale's School of Architecture and while there fell under the spell of architect Robert Venturi, who was throwing stones at the glass boxes of modernism and telling young architects to look to history for new ideas. Says Childs: ''Venturi opened our eyes to a whole past that not only had been forgotten, but had been prohibited to us.'' With his newfound respect for tradition, Childs spent the 1970s and early 1980s in Washington, D.C., designing structures for a city steeped in history. He made his name with his redesign of the two-mile Washington Mall, which houses the Capitol, monuments, and museums. This project brought him commissions for Jefferson Court, a complex of offices and shops in Georgetown, and for a new headquarters for U.S. News & World Report. He also designed the 1300 New York Avenue office building -- a $51-million, 12-story structure -- after a Renaissance palazzo. In the lobby a waterfall, inspired by the gardens of Villa Lante in Bagnaia, Italy, cascades from seven stories above into a marble pool surrounded by whimsical topiary spires and mock columns topped by huge marble balls. ''I'm a classicist,'' he admits unblushingly. ''If you want to see the cutting edge of architecture, you should go to ancient Rome.'' Childs loves columns, arches, and wedding-cake skyscrapers. To him the utmost architectural statement is to make a building ''handsome.'' He adds, ''The one thing an architect can do for a project is add art. And if we don't do that, we're clearly not necessary.'' Childs's reward for his success in Washington was the top design job in SOM's New York office in 1984. Soon after arrival he landed the biggest project of his career, the $230-million Worldwide Plaza in Manhattan's midtown that William Zeckendorf Jr. and his partners are building between Eighth and Ninth avenues. Childs's challenge is to create a livable city within a city, much as was done a half-century ago with Rockefeller Center, a few blocks east. Says he: ''The architecture of the future lies in making use of the best of the past.''

HELMUT JAHN: FLASH AND FASHION His peers refer to him as Baron von High Tech or, less flatteringly, as the Flash Gordon of American architecture, but Helmut Jahn, 47, just laughs. And why not? By far the most flamboyant and commercially successful architect of his generation, Jahn is watching his imaginative high-rises shoot up in cities throughout the U.S. and Europe. ''As an architect, you have to be an optimist, always trying to relate an exuberance and excitement in your buildings that will make our cities better places to live,'' he says. In New York alone he has five major buildings under construction whose floor space exceeds that of the Empire State Building. His portfolio includes the tallest building in Philadelphia -- the 63-story Liberty Place Tower, the first ever to rise above the statue of William Penn atop city hall. Add to that the tallest building in Continental Europe -- the 59-story Messe Tower in Frankfurt -- and you get the most prolific architect in America. What rankles competitors is Jahn's penchant for the sensational and his flair for self-promotion. Two years ago he appeared on the cover of GQ magazine, which ran a story claiming, ''Jahn dresses like he designs: to kill.'' He often garbs himself in gray European-cut suits with gray silk ties and handkerchiefs. His slick Italian loafers look more like ballet slippers than business shoes. He zips around Chicago in a red Porsche and rises at 5:30 to get in a four- or five-mile jog. The same flash and fashion appear in his buildings. He melds a Space Age look with traditional skyscraper lines, exploiting their contrasts so few could miss them. A typical Jahn touch: folding glass and stone curtain walls into octagons, rotundas, diamonds, and spirals. Liberty Place Tower looks like a Chrysler Building with its spire at the top, but it has a glass and granite facade. ''We give developers an image that sets their buildings apart,'' Jahn says. And he knows how to give a client what he wants. Whereas many architects will present the paying customer with a single drawing of a new building, Jahn prepares four or five sketches to give clients a choice. He has recently completed the Park Avenue Tower in midtown Manhattan, where IBM, which owns roughly 50% of the building, leases office space for training. Says Jahn: ''IBM has a very solid business image. But they didn't want to be thought of as stodgy and old-fashioned. They picked the building because they liked its forward-looking, optimistic design.'' When the building, including the pyramid at its top, is lighted at dusk, it has a futuristic glow, but Park Avenue Tower's overall obelisk shape makes a sweeping bow to the past. Born in Germany, the son of a Bavarian schoolmaster, Jahn came to the U.S. in 1966 to study at the Illinois Institute of Technology, where Ludwig Mies van der Rohe made the sleek glass high-rise famous. A year later Jahn, who still speaks with a thick German accent, joined Chicago's C.F. Murphy Associates, a firm of commercial architects. He prospered almost immediately on the strength of his prolific new design ideas and lightning-fast ability to sketch them. At the age of 33, he became executive vice president and director of planning and design. Six years ago the firm changed its name to Murphy/ Jahn. Today located in a 1920s office building, it employs 80 architects. Not surprisingly, this master builder wouldn't mind being the first architect to create a mega-skyscraper, a building that soars 200 or 300 stories. He has already included such a structure in his design for Donald Trump's Television City in New York, a gigantic seven-tower project, with one tower that looms 150 stories above the Hudson River. But Trump switched architects after the community objected to having such a mega-project in an already overcrowded residential neighborhood. Says Jahn: ''I think there will be a 200-story skyscraper someday. However, it will require a developer who will not think in conventional terms and for whom economic restraints won't apply.''

RALPH JOHNSON: THE REGIONALIST At an age when most young architects in big firms spend their days tediously drafting toilet elevations or window details for a skyscraper, Ralph Johnson, 38, already has a major Chicago high-rise to his name and four more towers under way. Johnson leapfrogged the slow process of apprenticeship at Chicago's prestigious Perkins & Will in 1984 when Rubloff Inc., a commercial developer looking to build a skyscraper on Wacker Drive in the West Loop area, took a fancy to his design over those of all his colleagues at the firm. Johnson believes strongly in regionalism, which means designing a structure to reflect the style of those surrounding it. He gave that first building, the $36-million, 30-story tower at 123 North Wacker Drive, a pyramid top to reflect the slope of the roof of the 57-year-old Civic Opera House located just across the street. Then he endowed the facade with a split personality. Its glass and aluminum curtain wall echoes the gigantic modernism of the Sears Tower, the world's tallest building, but the wall is edged with gray and red granite to mimic the city's solid turn-of-the-century stone skyscrapers. ''I don't like to label my buildings modern or postmodern,'' says Johnson. ''I consciously try to recall the old buildings of Chicago without being too literal. My work is a collage of the modern and the old.'' The summit of 123 North Wacker has a three-story atrium, which Johnson describes as a ''corporate penthouse in the sky.'' The pyramid is lit at night, and just below it, spotlights shine through decorative portholes in the building's skin, making 123 North Wacker a beacon in the Windy City. Besides being a creator of beautiful collages, Johnson is a technical wizard constantly searching for ways to make a building more efficient and thus more salable. At 123 North Wacker, for example, he equipped each floor with its own heating and cooling unit rather than installing the customary central system, which requires expensive duct work. The design allows tenants to control their own heat and air conditioning, resulting in lower energy costs and permitting them more flexibility in using the space. A floor that houses heat-generating computer equipment, for example, can receive more air conditioning, while other floors get less. Johnson became fascinated with architecture when he was a kid growing up in Chicago and riding his bicycle past a Frank Lloyd Wright house just down the street. At the Harvard Graduate School of Design he learned that buildings should be responsive to the people who work in them. Today Johnson argues that employees are more productive in buildings with big atrium spaces that bring in natural light, and open plazas where workers can relax, dine, or shop at lunchtime. He also lays out offices so that the boss can't hide in a corner but is visible to the rest of the troops. ''The purpose of architecture,'' he says, ''is to create better environments and make people happier. That's why you become an architect in the first place -- to do something people enjoy.''

WILLIAM PEDERSEN: THE POSTMODERNIST When he was a boy in St. Paul, William Pedersen saved up $20 to buy a pair of special blades to attach to his old hockey skates. He didn't want to skate faster; he just loved their sleek, curved line. The shape of those skate blades has been celebrated in a number of his projects, including 333 Wacker Drive in Chicago, which he designed in association with Perkins & Will. Finished in 1983, this 36-story, $60-million office built by Urban Investment & Development Co. was Pedersen's first high-rise and the beginning of a national reputation for his firm, Kohn Pedersen Fox. Paul Goldberger, the architecture critic of the New York Times, says of the firm's work: ''Kohn Pedersen has managed to do what few architectural firms have -- to make a lot of money and to produce first-rate architecture.'' A poll among architects last year by Progressive Architecture magazine listed two of KPF's commissions among the five most significant buildings designed in the past five years. Now Pedersen, 49, is shying away from sleek, modernistic designs like 333 Wacker and is blending contemporary and classical elements in his work, a style most often called postmodernism. Says he: ''What classicism teaches us is to be concerned with scale, the relationship of a human being to the building and the parts of the building to each other.'' His Procter & Gamble headquarters in Cincinnati seems to sum up KPF's current thinking best. It is a six-story, L-shaped structure with twin 17-story octagonal towers rising on either side of the corner of the L. Its limestone facade and pyramid roofs on the towers enable the building to fit seamlessly with P&G's old headquarters next door. A five-acre park with walkways and benches gives employees a pleasant lunchtime retreat. Today's C.E.O.s, says Pedersen, are becoming less concerned with building corporate monuments and more interested in architecture that adds to the quality of life. Procter & Gamble understood this when building its Cincinnati headquarters. Says Pedersen: ''The C.E.O., John Smale, wanted to give something back to the community. With Procter & Gamble we could have easily built the tallest building in town. Instead we designed a relatively small building with a large park, which provides a great amenity to the city.'' Pedersen graduated from MIT in 1963 with a master's degree in architecture and worked for a number of architects, including I. M. Pei, renowned for his elegantly modern skyscrapers. In 1976 he decided to start his own shop, but the New York building industry was so dead that he nearly gave it all up to return to those St. Paul winters. Thanks to his partner Eugene Kohn, the legendary salesman who landed a commission from ABC-TV to design an office building and a studio on Manhattan's Upper West Side, Pedersen got his big break, and the firm was in business. Since then KPF, driven by Pedersen's designs and Kohn's silver-tongued salesmanship, has grown to 150 architects in New York City and has designed over 20 major buildings in the U.S., England, and West Germany. Pedersen, who has a Midwestern, boyish quality about him, lives in New York with his wife and two children. When he's not designing beautiful buildings, he collects beautiful English Regency and French Empire furniture that he admires for its elegant lines. He also plays classical piano, a hobby that he says is closely related to architecture: ''Designing a building is like interpreting a piece of music. You have to think about how each detail of a building, like each musical phrase, is begun, how it is ended, and the way it's sculpted.''

ROBERT A.M. STERN: THE SCHOLAR No living architect fits the description of a Renaissance man better than Robert A.M. Stern. He creates homes, resorts, and high-rises, teaches architecture at Columbia University, has written three books, and has starred in his own public television series, called Pride of Place. After Philip Johnson and I. M. Pei, Stern, 48, is probably America's best-known master builder. Yet his ego remains in shape. ''Architecture is a business and an art, and I'm a very pragmatic person,'' he says. And then he takes a poke at Frank Lloyd Wright: ''I don't stamp on a table, I don't wear a cape, I don't walk with a stick.'' What Stern does do is take a very scholarly approach to his art. Says he: ''I like to think of myself as someone who uses history in a creative way to make modern solutions. I'm not just pasting moldings on buildings. I hate jokes with the past. I'm interested in having people look at my work and say, 'This belongs here.' Of course I'd also like them to say, 'Only Bob Stern could have made such a sensitive building.' '' He graduated from Yale's School of Architecture in 1965 and began to make a name designing turn-of-the-century-style, gray-shingle beach houses in the Hamptons for wealthy New Yorkers. By the early 1980s he had branched into office buildings and resort projects. ''Large-scale buildings are best designed by people with experience working on a smaller scale. They have a greater sense of the individual,'' he says. His studio of 95 architects, who work out of a converted warehouse on Manhattan's Upper West Side, has recently produced an office building in Framingham, Massachusetts, that developer Gerald Hines built. The gray, peach, and pewter striped glass cube playfully picks up the nearby neon-lit commercial strip cluttered with Burger Kings and gas stations. But the classical facade with its rounded pediment and columned entryway suggests Stern's unmistakable way with history. Corporate clients and developers like Stern because his buildings do fit in and are usually approved without fuss by cantankerous community planning boards. In the early 1980s Stern saved an office project for a developer in La Jolla, California, after 13,000 residents signed a petition against it before it had even been designed. The community feared the building would be a cold glass box, out of place in a quaint Spanish-style town. Stern designed a Spanish colonial building with an open-air courtyard that fitted right in with La Jolla's architecture and allayed the community's fears. Now Stern is turning his attention to skyscrapers. For developer Hines he has created one of two towers in Boston's Back Bay that will house the headquarters of the New England, formerly known as New England Life Insurance. Philip Johnson designed the other tower. Stern's 22-story structure with its columns and arched mullioned windows reflects the elegant 19th-century townhouses lining the streets of Back Bay. The tower is also stepped back like a 1920s office building to help it fit into the community more agreeably. ''The human cry was to make a Boston building,'' Stern says. ''You have to be a bit of an interpreter and a scholar to do that.''