Seizing the title of "world's tallest building"-be it Joseph Pulitzer's 20-story New York World newspaper building in lower Manhattan in 1890, the Empire State Building in 1931, or Kuala Lumpur, Malaysia's gargantuan Petronas Towers in 1998-has always been about pushing the limits of architecture and engineering. But three years after the attacks of September 11 demonstrated how vulnerable such buildings are to terrorists, a surprising new competition is under way. The latest skyline king is a vaguely pagoda-like tower in Taipei, Taiwan, called Taipei 101 (see "Inside Taipei 101," below). Slated for occupancy this fall, the 101-story structure stands 508 meters tall, more than half a football field higher than Petronas. On the horizon are even taller skyscrapers, including the Freedom Tower proposed for New York City's ground zero, and a business and residential colossus in Dubai, United Arab Emirates.

It's getting crowded at the top: several other massive skyscrapers, while not quite record-setters, have risen in Asian cities in the past decade, with another under construction in Shanghai, China. Indeed, eight of the world's ten tallest buildings are now in Asia. "Some Asian economies have grown more wealthy than before, and they now want to express their identities," says C. P. Wang, the architect of Taipei 101. "To me, a skyscraper is an easy way to do that." Indeed, proclaims Gail Fenske, an architecture professor at Roger Williams University in Bristol, RI, the world is in the midst of "a new skyscraper frenzy."