Hines Interests already has lured Kirkland & Ellis away from the Aon Center to 600,000 sf in its riverfront building once it is completed in 2009. In addition to office space, plans call for 13,000-sf of retail space, which most likely will include a restaurant.

However, Hines Interests' office tower will dwarf surrounding low- and mid-rise properties sharing the riverfront, notes plan commission member Allison Davis. Taller buildings already line the riverfront a quarter-mile to the east, and Trump International Hotel & Tower will dwarf both Marina City and 330 N. Wabash Ave. Closer to 300 N. LaSalle St., though, is the 3.5-million-sf Merchandise Mart, a mid-rise building, as is the redeveloped Reid-Murdoch building at 325 N. LaSalle St. and Helene Curtis building at 325 N. Wells St.

"The planning department has always taken the position that along the river, we would try to encourage tall buildings," says 42nd Ward Alderman Burton Natarus. "This is a tall building. This is a magnificent building. What's there now is kind of shabby."