Unisys Corp. is moving its headquarters and 225 management jobs to Two Liberty Place in Center City from Blue Bell.

"We're welcoming them back to Philadelphia," said Stephanie Naidoff, the city's commerce director. Naidoff said the city would give Unisys up to $1 million in yearly job-creation tax incentives.

"It's a wonderful stamp of approval, a major suburban company moving back to Philadelphia," she added.

Naidoff noted that the computer-services company traces its roots to a firm founded in the 1940s by computer pioneers from the University of Pennsylvania.

"We wanted to change the face of Unisys to our clients and partners, and to people we're recruiting," Unisys chief executive officer Joseph McGrath said in an interview yesterday. After 35 years in a former computer factory, "we need a high-tech space."

Naidoff said Mayor Street and other city officials had been wooing Unisys since mid-2006. The negotiations, she said, "were like a roller coaster."

Street had planned to announce the move at a news conference today, but that has been canceled, said Naidoff and Nadine Bonner, a spokeswoman for the mayor.

McGrath said Center City was convenient to Amtrak trains serving Washington, home to Unisys' federal-government clients, and to New York's financial district.

"We looked everywhere. We looked all up and down [Route] 202, we looked in Conshohocken, we looked around Center City," McGrath said. "The energy, the restaurants, the shows - it's very hard to create that energy out here in the suburbs. It's uniquely a Center City thing."

He said the new offices, encompassing the 34th, 35th and 36th floors and part of the 27th floor at Two Liberty Place, would include "hoteling" space, for Unisys workers serving local clients, and a demonstration center for Unisys products for out-of-town clients and business partners.

Unisys employs 775 in Blue Bell. The company is considering alternative locations in the Philadelphia suburbs for the more than 500 who will not make the move to Center City.

The company also employs 650 at its Malvern technology research-and-development center. About 1,000 others work at Unisys offices or with clients in the Philadelphia area. Worldwide, the company has 29,500 employees.

Brokers had sought to lease Two Liberty Place for more than $30 a square foot. After negotiations, Unisys agreed to pay rates in the high $20s, said Brian Katz, president of America's Capital Partners, Unisys' new landlord.

The rate compares favorably with recent leases in the mid-$30s at Mellon Bank Center nearby, said Kenneth R. Zirk, senior vice president at Jones Lang LaSalle Inc., Unisys' corporate real estate representative.

He said Two Liberty Place's Westin Hotel provided space for visiting Unisys clients and meetings. "The image and branding was critical to Unisys' decision," Zirk said.

CB Richard Ellis Group Inc. was leasing broker for building owner America's Capital, Katz said.

The city has attracted few big company headquarters in recent decades. Last spring, Lincoln National Corp. said it was moving 400 headquarters employees from Philadelphia to Radnor, closer to the suburban home of its then-CEO Jon Boscia.

Katz's company bought Two Liberty Place in 2005 and, with other investors, converted the 40th to 57th floors into residential condominiums. Other office tenants include law firm Buchanan Ingersoll & Rooney P.C. and the Grosvenor real estate management company.

Landlord Katz praised Street and Mayor-elect Michael Nutter for helping woo Unisys, and he said the city would have an easier time attracting employers if Nutter were able to continue Street's policy of reducing the city wage tax.

Street and Nutter were not immediately available for comment.

Contact staff writer Joseph N. DiStefano at 215-854-5194 or jdistefano@phillynews.com.