Members of Cambridge City Council signed a contract finalizing the details of Richard C. Rossi’s appointment as Cambridge’s next City Manager at the end of Monday night’s City Council meeting.

Rossi, currently the Deputy City Manager, was tapped for the position last December nine months after current City Manager Robert W. Healy announced his retirement.

The contract stipulates that Rossi will take office July 1 and will serve as City Manager for three years.

Cantabrigians crowded into City Hall for the meeting, which focused primarily on proposed construction in Kendall Square.

Despite fierce opposition from some Cambridge residents concerned about noise and pollution, the City Council unanimously voted to allow the pharmaceutical company Millennium to construct a new laboratory in Kendall Square.

In order to move the plans forward, the Council amended its current zoning ordinances. Millennium will construct its new 230,000 square foot building in an area previously designated as residential space.

The City Council’s decision ended two years of negotiations between Cambridge and the companies Millennium and Forest City, the real estate development company that will construct the complex.

Negotiations broke off last spring when the Council realized that the development would jeopardize 168 units of affordable housing. Forest City then returned to the table this fall with a proposal that would not only preserve those 168 units but also create 25 additional units of affordable housing.

“What we see before us is a very different petition than that that was filed originally,” said Councillor David P. Maher, who led the negotiations on behalf of the City Council.

Maher urged his fellow councillors to support the zoning amendment, calling Millennium “one of the top employers in the greater Boston area.”

Some Cantabrigians in attendance raised concerns about the pollution and noise that would result from construction, while others stressed that the new complex would foster job creation and scientific research.

“Millennium Pharma is not a company that makes Viagra,” psychology professor Daniel T. Gilbert said at the meeting. Gilbert said his wife currently works at Millennium researching a cure for pancreatic cancer.

—Staff writer Sonali Y. Salgado can be reached at ssalgado@college.harvard.edu. Follow her on Twitter @SonaliSalgado16.