Background Few population-based studies have examined the behavioral and psychosocial predictors of long-term weight-loss maintenance. Purpose The goal of this study was to determine the prevalence and predictors of weight-loss maintenance in a biracial cohort of younger adults. Methods This study examined a population-based sample of overweight/obese African-American and white men and women who had <5% weight loss between 1995 and 2000. Subsequent changes in weight, physical activity, and behavioral and psychosocial factors were examined between 2000 and 2005. Analyses were conducted in 20082009. Results Among the 1869 overweight/obese individuals without major disease in 1995, a total of 536 (29%) lost <5% between 1995 and 2000. Among those who lost weight, 34% (n=180) maintained at least 75% of their weight loss between 2000 and 2005, whereas 66% subsequently regained. Higher odds of successful weight-loss maintenance were related to African-American race (OR=1.7, p=0.03); smoking (OR=3.4, p=0.0001); history of diabetes (OR=2.2, p=0.04); increases in moderate physical activity between 2000 and 2005 (OR=1.4, p=0.005); increases in emotional support over the same period (OR=1.6, p=0.01); and less sugar-sweetened soft drink consumption in 2005 (OR=0.8, p=0.006). Conclusions One third of overweight men and women who lost weight were able to maintain 75% or more of their weight loss over 5 years. Interventions to promote weight-loss maintenance may benefit from targeting increased physical activity and emotional support and decreased sugar-sweetened soft drink consumption. © 2010 American Journal of Preventive Medicine.