Innovation Park, also known as Rancho Vistoso Neighborhood 3, consists of 810 acres. Its boundaries are north of Tangerine Road, west of North Oracle Road, south of Rancho Vistoso Boulevard and east of Big Wash. It is already home to the town's top employer, Ventana Medical Systems Inc.

Unless Oro Valley is successful with annexation, Innovation Park is the town's last opportunity to develop economically, said Jerry Bustamante, president and CEO of the Northern Pima County Chamber of Commerce, at a Sept. 19 public hearing.

Innovation Park has 190-plus acres designated for commercial office park use. That is the largest portion of undeveloped land designated for that use in Oro Valley, wrote senior town planner Matt Michels in a Sept. 19 memo to Oro Valley's Town Council.

Less than 2 percent of the town's total area is designated for that use, and the majority of those acres is already developed, making Innovation Park the only area that has a concentration of land designated for commercial office park development, he wrote.

Innovation Park was the subject of two separate Town Council votes at a Sept. 19 public meeting.

In one vote, the council approved a general plan amendment that will change the designated land use for 144 acres of Innovation Park. That amendment will affect the overall layout of nearly 440 acres in the business park.

Seventy-four acres that were designated for development will be designated as open space, and 70 acres that were designated to remain open space will be designated for development.

Developer Venture West, Rancho Vistoso master developer Vistoso Partners and Ventana Medical Systems own the land and initiated the amendment.

The amendment will consolidate developable parcels that currently are scattered into larger parcels, making the parcels more attractive to high-end corporations, said Paul Oland of The WLB Group Inc. The WLB Group is processing the plans for the site and represents the landowners.

The general plan amendment also will move development away from Big Wash, Oland said, allowing more area around the wash to remain natural.

The economic-development factor has played heavily in public discussions of the amendment.

Developing the area as a corporate center with professional-level employment is "one of the highest economic-development priorities of the community," wrote David Welsh in a June 29 memo to the the town's Planning and Zoning Department. Welsh is Oro Valley's economic development administrator.

Besides Ventana Medical Systems, other Innovation Park companies include Northwest Medical Center Oro Valley and Integrated Biomolecule Corp. The hospital is Oro Valley's fourth-largest employer, according to the town's Web site, www.townoforovalley.com.

In addition, pharmaceutical company Sanofi-Aventis will soon join Innovation Park.

In its second vote on Sept. 19, the Oro Valley Town Council approved a development plan for Sanofi-Aventis' 110,350-square-foot, two-story technology and research center, which will be built in Innovation Park.

The research lab and office space will house the company's Combinatorial Technologies Center, which has outgrown its current space in Oro Valley, said Beth Koch, site director. It is currently located at 1580 E. Hanley Blvd.

The development will be designed so Sanofi-Aventis has room to expand in a second phase, if it decides to, said David Little of The WLB Group.

The company plans to build its new center according to the U.S. Green Building Council's Leadership in Energy and Environmental Design certification standards, Little said. That means that it will be built according to federally set guidelines for more environmentally sound building.

Sanofi-Aventis is already Oro Valley's 10th-largest employer, according to the town's Web site. It employs 67 associates, 25 of whom live in Oro Valley, Koch said.

The company plans to add more than 40 employees, most of whom will work in scientific fields requiring advanced education, Koch wrote in an Aug. 30 letter to Oro Valley Mayor Paul Loomis.

Koch was writing to request an economic-development agreement that would rebate some construction sales tax generated by the Sanofi-Aventis development.

"In light of the overall direct and indirect planned investment in the community, Sanofi-Aventis is requesting the rebate of at least 1 percent of the 4 percent construction sales tax collected by the town," Koch wrote. She estimated that the 1 percent would equal at least $360,000.

Oro Valley's Town Council went into executive session on Sept. 19, holding a closed-door discussion on the economic-development agreement.

The next day, Loomis referred to Sanofi-Aventis' impact on Oro Valley in his State of the Town speech.

"This leading international pharmaceutical research company will build a $60 million facility in Oro Valley and employ more than 100 individuals earning professional wages," Loomis said.

That one company will bring more than $100 million to the region, he said.