This chapter reviews and assesses current empirical evidence of marine protected area (MPA) effects on fisheries. First, we briefly describe the mechanisms by which MPAs may affect fisheries. Second, we synthesize empirical evidence of those effects, essentially transfer of exploitable biomass from MPAs to fished areas and ensuing changes in catch and effort patterns. Lastly, we discuss this evidence, highlighting the strengths and weaknesses of MPAs for fisheries management based on current empirical knowledge.