This chapter examines how international law, along with sanctions regimes, can interfere with the quest for sustainability by surprisingly stopping progress on global development goals. While the Sustainable Development Goals and the Paris Agreement now make sustainability a main goal, international sanctions are seen as conflicting tools in that field. Using research and case studies from Iran, Russia, North Korea and Venezuela, it focuses on how sanctions prevent effective action in climate, health, energy transition and environmental protection. It looks at how sanctions have evolved, from covering all groups to just specific targets and asks whether these actions still follow basic rules of international law. The chapter ultimately calls for more sustainable thinking about sanctions and suggests innovations including impact assessments, special carve-outs for humanitarian action and ESG standards mechanism. Because we are facing climate, conflict and weakening institutions all at once, the chapter suggests supporting both peace and sustainable development more thoroughly.