The core parts of Boston, and some of the adjacent towns, definitely yes. MBTA's current troubles aside, there's a good network of public transit to get you within a few blocks of your destination, and probably you can access the system within a similarly short distance.

Some of the more outlaying parts ... maybe yes?

Overall, it's got to be one of the more walkable cities in the U.S.

...

Compared to most of Europe it's pretty shit, though.