Dieting is one of the most widely studied risk factors for eating disorders (EDs). Determining whether dieting increases risk for EDs is crucial because 30% of young women report dieting and low‐calorie diets are prescribed to treat obesity, often resulting in significant weight loss and improved health. The studies reviewed in this chapter illustrate the importance of documenting the validity of measures with methods that are less subject to distortion by social desirability. The chapter underscores the hazards of relying solely on prospective studies when making etiologic inferences. It suggests several directions for research. First, researchers should seek to identify the third variable that is tapped by dietary restraint scales that truly increases risk for onset of bulimic pathology, because this will advance our understanding of the etiologic processes that cause EDs. Second, it will also be important to conduct experiments that manipulate specific weight loss behaviors.