List of tallest buildings
The international non-profit organization Council on Tall Buildings and Urban Habitat (CTBUH) was formed in 1969 and announces the title of "The World's Tallest Building" and sets the standards by which buildings are measured. It maintains a list of the 100 tallest completed buildings in the world. The organization currently ranks Burj Khalifa in Dubai as the tallest at . The CTBUH only recognizes buildings that are complete however, and some buildings included within the lists in this article are not considered finished by the CTBUH.
List of tallest buildings and structures
A major controversy erupted upon completion of the Petronas Towers in Kuala Lumpur, Malaysia in 1998. These twin towers, at , had a higher architectural height (spires, not antennas), but a lower absolute pinnacle height and a lower top occupied floor than the Willis Tower in Chicago. Counting buildings as structures with floors throughout, and with antenna masts excluded, the Willis was still considered the tallest at that time. Excluding their spires, which are higher than the flat roof of Willis, the Petronas Towers are not taller than Willis. At their convention in Chicago, the Council on Tall Buildings and Urban Habitat (CTBUH) found the Willis Tower (without its antennas) to be the third-tallest building, and the Petronas Towers (with their spires) to be the world's two tallest buildings.