The present study sought to evaluate the effects of feedback and positive social reinforcement on the performance of restaurant drive-thru window order-takers in asking customers to "upsize" their order at a specific prompt. A multiple baseline across settings was followed by the introduction of an intervention of weekly performance feedback and social reinforcement delivered by restaurant managers. At the first restaurant, asking to "upsize" increased from a mean of 65% to 96%. At the second restaurant, asking to "upsize" increased from a mean of 81% to 93%. Implications of performance feedback for increasing employee performance and the financial profits of an organization are discussed.