The major objective of this study is to determine if two techniques for monitoring physical activity and energy balance promote the maintenance of weight loss in healthy overweight and obese individuals. The study compares two approaches designed to help individuals monitor physical activity and to adjust their calorie intake to maintain a reasonable energy balance (bodybugg® & Step Diet Book systems). Full subject participation in the study spans two years. Participants periodically report to a pre-arranged location to be measured by a qualified fitness professional for height, weight, circumferences, and estimated body fat using a bioelectric impedance scale (body fat scale).