A phased rapid transit system could connect institutional and commercial centers in an arc around greater Boston’s urban core, local pundits from the public, private and non-profit sectors said Monday at a town hall meeting at the Kennedy School of Government.

The current transit system in the Greater Boston area is a radial system, with subway and commuter rail lines spreading out like spokes from hubs, such as Park Street and North Station. This idea of an urban ring would create transit lines running in a circle around the urban area.

“Boston is sprawling as much as any region in this country. The urban ring is key to absorbing future rounds of growth,” said David Dixon, the incoming president of the Boston Society of Architects.

A proposed urban ring transit system would start in East Boston and run around Chelsea and Everett to Sullivan Square in Charlestown, then go through North Point, East Cambridge, and Kendall Square and across the B.U. Bridge into Boston. The ring would continue through Fenway, the Longwood Medical Area (LMA) and Ruggles and end up in South Boston.

Members of the panel said the Boston area’s transit services are inadequate, with a need to reduce pressure on a subway system that is well-used and overcrowded.

Participants said urban ring transit would allow employers in the corridor to better recruit and retain employees, with better transit around the corridor also promoting development and creating jobs. The urban ring corridor is now home to 300,000 people and 350,000 jobs.

“It’s not just about getting people from Roxbury and Chelsea to the other side of town. It’s about bringing the jobs to you,” said M. David Lee, an adjunct professor of urban planning and design at the Graduate School of Design (GSD) who has been advocating for an urban ring for a decade.

In addition, the proposed urban ring would connect many of greater Boston’s major hospitals and health services. Boston City Hospital, Boston University Medical Center, and the LMA health services—including Children’s Hospital, Beth Israel Hospital and Harvard Medical School—would all be accessible via the prososed project.

The city of Cambridge strongly supports the urban ring project for its potential to reduce automobile traffic, according to Susanne Rasmussen, the director of the city’s community development department.

“The urban ring shifts more people from cars to transit than any other project projections,” Rasmussen said.

Since automobiles are the biggest cause of smog and greenhouse gases, the creation of an urban ring could have significant environmental benefits, said James H. Wickersham, a lecturer in urban planning at GSD and director of the state’s Mass. Environmental Policy Act office.

Wickersham also stressed the importance of developing bike routes and sidewalks so people have the options of cycling or walking. Boston is not easily accessible by bicycle, and the city has been rated the worst in the country for cyclists by Bicycling Magazine.

The proposed urban ring would come in three phases, said MBTA project manager Peter C. Calcaterra. The first phase would create about 12 new crosstown bus routes, including buses that run on compressed natural gas, a cleaner alternative to diesel fuel.

In the second phase, the project would build designated bus lanes to speed up bus service in what is called a bus rapid transit system.

The third phase would develop light rail lines around much of the urban ring corridor.