The long-awaited New Brunswick Performing Arts Center has opened its doors, marking the debut of a $172 million, mixed-use project that is poised to transform the city’s famed arts district.

A crowd of stakeholders, supporters and dignitaries on Wednesday packed the lobby of the 23-story building on Livingston Avenue, which has brought new performance venues, more than 200 apartments and office space to downtown New Brunswick. The milestone follows some 22 months of construction and results from a complex array of private and public financing sources, a partnership that was celebrated during a grand opening ceremony.

“Tonight is all about the arts, community, partnership and leadership,” said Chris Paladino, the president of New Brunswick Development Corp., the organization behind the 450,000-square-foot project and so many other high-profile developments in the city.

Designed by Elkus Manfredi Architects, the complex occupies the site of the former George Street Playhouse and Crossroads Theater. It is now the home of both theater companies, which are longtime fixtures in the city, along with the American Repertory Ballet and Mason Gross School of the Arts at Rutgers University-New Brunswick.