This article assesses the potential for incomplete definitions of resource use to influence estimates of nonuser willingness to pay (WTP), with an emphasis on resources for which an exhaustive set of uses may be difficult to characterize. The data are drawn from a stated preference analysis involving coastal wetland restoration. Results suggest that mechanisms used to distinguish users and nonusers of wetland services may influence estimates of nonuser WTP and that for some attributes, traditional distinctions between user and nonuser WTP may have arguable empirical justification. More broadly, results suggest that relationships among use behaviors and restoration values may be more complex than are typically assumed and point to limitations in methods frequently used to distinguish user and nonuser WTP.