Over the last ten to fifteen years, economists and legal scholars have become increasingly interested in and sensitive to behavioralist insights. In a companion article, Jon Hanson and Douglas Kysar argued that those scholars have nevertheless given short shrift to what is, at least for policymaking purposes, perhaps the most important lesson of the behavioralist research: individuals' perceptions and preferences are highly manipulable. According to Hanson and Kysar, one theoretical implication of that insight for products liability law is that manufacturers and marketers will manipulate the risk perceptions of consumers. Indeed, to survive in a competitive market, manufacturers and marketers must do so. In this Article, Hanson and Kysar present empirical evidence of market manipulation--a previously unrecognized source of market failure. The Article begins by surveying the extensive qualitative and quantitative marketing research and consumer behavioral studies that discern and influence consumer perceptions. It then provides evidence of market manipulation by reviewing common practices in everyday market settings, such as gas stations and supermarkets, and by examining familiar marketing approaches, such as environmentally oriented and fear-based advertising. Although consumers may be well-aware of those practices and approaches, they appear to be generally unaware of the extent to which those tactics are manipulative. The Article then focuses on the industry that has most depended upon market manipulation: the cigarette industry. Through decades of sophisticated marketing and public relations efforts, cigarette manufacturers have heightened consumer demand and lowered consumer risk perceptions. Because consumers are aware that smoking may pose significant health risks, the tobacco industry's success in manipulating risk perceptions constitutes especially strong evidence of the power of market manipulation. The Article concludes by arguing that the evidence of market manipulation may justify moving to a regime of enterprise liability. Indeed, according to Hanson and Kysar, the evidence of market manipulation confirms the intuitions of the first generation of product liability scholars, who worried about manufacturers' power to manipulate and called for just such a regime.