1. IPD Program: This program will be directed by health counselors from Johns Hopkins University. For Months 1 to 3, participants will attend a group or individual meeting with a counselor each week. For Months 4 to 6, meetings will be held three times a month; after Month 6, meetings will occur twice a month. Some of these meetings may be held over the phone or by e-mail. Participants will keep a food and exercise diary and they will enter their weight and calorie consumption on the study Web site. Study researchers will provide participants' doctors with relevant information on participants' weight loss.