Socioeconomic evaluation of marine protected areas (MPAs) aims to identify and measure the social costs and benefits created by the MPA. Thus, an overall assessment and its breakdown within the society can be determined. This chapter first presents the main tools for the socioeconomic evaluation of MPAs. The two main types of tools are the techniques for the evaluation of non-market values, and bioeconomic models. Next, the chapter addresses the problems inherent in the measurement of the non-market values meant to maintain the MPAs. It describes the problems inherent in modeling the bioeconomic processes which the MPAs are supposed to influence. For each case, the chapter outlines the main adaptations used in the attempt to resolve, or at least to reduce, these difficulties. © ISTE Ltd 2015. All rights reserved.