Boston Planning and Development Agency

Boston’s planning board on Thursday declined to approve a proposal to build 218 apartments on what are now vacant lots in Mission Hill, telling the developer it needs to win more community support.

Arthur Jemison was attending Amherst Regional High School in western Massachusetts when his parents, who had migrated from Detroit, split up. His father James, an instructor at the nearby UMass campus, had been bringing in most of the family’s income.

In the city of Boston, there is one agency that might have more power than anything else over what you see around you: the buildings, parking lots, apartments and parks that shape your neighborhood.