ABSTRACT
Although science diplomacy has been gaining relevance in foreign policy to solve environmental challenges, critical questions concerning what different instruments mean under the term 'science diplomacy' and whether science diplomacy does contribute to the progress in solving environmental issues remain unanswered. We explore those questions by linking science diplomacy salient features through documentary analysis of international instruments addressing the plastics pollution in the ocean. We find that from a science diplomacy and multi-level governance perspective, the responsibilities and capabilities of emergent actors of cross-level governance are also important, leading to more attention being paid to changes in the role of national authorities, away from passive leadership to cross-cutting coalitions supported by the salient features of science diplomacy, and redefining dominant discursive approaches that have framed plastics waste. Points for practitioners: As a result of the cost and limitations of the current international mechanisms, there is currently no incentive for individual countries to take action against marine plastic pollution.Science diplomacy and multi-level governance can contribute to international cooperation, foreign policy and national strategies.Leading efforts to engage countries with fewer scientific and technological capabilities could benefit countries' foreign policy.
