Policymakers and marine managers are increasingly using MPAs and marine reserves to achieve better conservation outcomes for marine areas. As these areas grow in number, it is important to analyze whether they are in fact achieving their desired outcomes and what factors led to their success. One major study published this year identified five characteristics of MPAs that achieved statistically significant outcomes on fish population metrics, including: “no take, well enforced, old (>10 years), large (>100km²) and isolated by deep water or sand” (Edgar et al. 2014). Two analyses of New Zealand’s system of marine reserves, which has now been in place for several decades, indicate unexpected benefits for scientists and scientific research. NZ’s no-take reserves have effectively served as “control” areas without which researchers would not have been able to draw fully informed conclusions. CCAMLR should consider these findings as they discuss the current Ross Sea and East Antarctica proposals, as well as future MPA proposals, to ensure that Southern Ocean MPAs will likewise achieve their desired conservation and scientific outcomes.