This study investigated whether informing obese individuals that they would lose only modest amounts of weight would lead them to adopt more realistic weight loss expectations. At a screening interview, 53 obese women reported that they expected to lose the equivalent of 28% of their initial weight during 1 year of treatment with the medication sibutramine. Prior to beginning treatment, participants were informed, both verbally and in writing, that they could expect to lose 5% to 15% of initial weight, the loss typically induced by current behavioral and pharmacologic approaches. This information, however, had little impact on their weight loss expectations when assessed on subsequent occasions. Results are discussed in terms of the origins, clinical significance, and potential malleability of obese individuals' weight loss expectations.