If a volunteer is randomly assigned to receive MBSR, he or she will be asked to attend 8 class sessions of training which will last 2 hours each. He or she will also be asked to attend a 5 hour retreat. In MBSR classes, you will receive instruction in mindfulness based body scan meditation. In addition, a subject assigned to MBSR will receive instruction in sitting meditation and in gentle yoga. Participants in both classes will also be asked to reflect on their meditation experiences during class and will be asked to consider carrying out a home practice during the week, outside of class. MBSR and body scan classes will meet at a meditation class facility convenient to a red line T stop in Cambridge.