We examine the state of ocean energy in 2009 and consider its potential as a source of renewable energy. We provide a background on the current state of technology and commercial development, and examine the implications for law and policy of the re-emergence of ocean energy as a source of renewable energy in 2009. In the 1970s much of the academic and policy literature highlighted jurisdictional uncertainty surrounding ocean energy under international law. This is not the case today. Although some questions remain with respect to navigation rights, most questions surrounding the nature and extent of coastal State jurisdiction in relation to ocean energy have been resolved by the 1982 United Nations Convention on the Law of the Sea. Instead we argue that one of the biggest challenges faced by ocean energy today is the uncertain state of regulation under domestic legal systems. We highlight issues requiring attention by policy-makers and legislators, including managing hazards to navigation, providing further financial incentives for wide-scale commercialisation of this technology (such as increased research and development funding and feed-in tariffs) and managing ocean energy's relatively benign environmental impacts.