We post specific volunteer opportunities at this link: Volunteering.
The BU School of Public Health (BUSPH) maintains a database for SPH students looking to complete a practicum. Many of the positions require that you are an SPH student, but well-qualified, enthusiastic undergraduates could probably get in too. Another place to start would be Idealist.org, a mammoth of a website. Some popular summer internships in the area are at Partners in Health, the Clinton Foundation, AIDS Action and Health Care Connection. Be forewarned, they are very competitive; here is the list of 2007 summer interns at Partners in Health.
Many more volunteer/internship opportunities are available in Boston, but they are not as publicized. I would recommend making contacts with individual people at BU and the BU School of Public Health who would be able to relay an internship before it becomes too publicized. Many professors at BUSPH, I’ve found, are more than happy to speak to undergraduates, and are more than willing to talk more about public health and other volunteer/internship opportunities.
Global Health:
Two 500-pound gorillas in the international public health scene reside in Boston. Partners in Health, of which Dr. Paul Farmer is the co-founder, is temporarily located in the Prudential Center as their offices on the Harvard Medical School campus are renovated. The Clinton Foundation‘s HIV/AIDS Initiative is located in nearby Quincy, MA. Both John Snow International and Management Sciences for Health provide technical guidance and training to global health practitioners, and are located in Boston-proper.
Domestic Public Health:
A journal article by Dr. Paul Farmer and others explains how public health in inner-city Boston and rural Haiti are similar and not-so-similar. My boss at DotWell, a public health organization serving the citizens of inner-city Boston, wished that everyone who was interested in international public health spend a few years working in inner-city US cities (Alex).
Boston Public Health Commission
Massachusetts Department of Public Health
DotWell (please contact Alex at aok1425@bu.edu)
Any of the local community health centers in Boston (a comprehensive list can be found here):