Contemporary technologies for offshore electricity generation and transmission enable sea uses of types and at scales that could not have been envisaged when the text of UNCLOS was agreed. The chapter considers whether UNCLOS is able to accommodate the offshore renewables revolution. It focuses on offshore wind energy, which is likely to see massive growth during the next three decades as the world decarbonizes. The review finds that UNCLOS does not always make adequate legal provision for them. Support will be needed from national laws, interstate agreements, and resolutions and guidelines of international organizations such as the International Maritime Organization to fill gaps in the law, clarify uncertainties and to meet challenges posed by offshore wind’s growth. Further regulation by states of offshore wind will also be needed to address the environmental effects of relevant development in line with duties for marine environmental protection, and to answer difficult legal questions raised by the pursuit of development that may itself cause significant environmental harm to address the environmental threats posed by climate change.