We examine the susceptibility of consumers' willingness-to-pay (WTP) and willingness-to-accept (WTA) judgments to influence by arbitrary anchors. The results of four studies suggest that, although circumstantial differences between buying and selling decisions can lead to systematic differences in susceptibility to anchoring effects, the principles governing the impact of anchoring on WTP and WTA judgments are essentially the same. In particular, robust anchoring effects are observed when the anchor relates to the focal source of uncertainty. Further, WTP and WTA judgments are most susceptible to anchoring (and endowment) effects under uncertainty about the desire to trade. The implications of this research for our understanding of anchoring and endowment effects are discussed.