The ocean is Earth's greatest climate mitigator, but it cannot do its work without biodiversity. Yet, accelerating climate change, unsustainable fishing, and widespread plastic and other pollutants, combined with increased resource demands, are threatening life throughout our global ocean. This is particularly acute in the two-thirds of the ocean (the high seas and seabed below) located beyond national boundaries, and as such, no state can solve these problems alone. Since 2018, member states of the United Nations have been crafting an international treaty to protect high-seas biodiversity and to ensure that human pressures are kept to a level that sustains this variety. Last month, the fifth and supposedly final session of the UN Intergovernmental Conference fell short of this goal. Unfortunately, disagreements on fundamental issues meant that negotiators ran out of time. Achieving a timely treaty requires resuming the dialogue as soon as possible with more visible public and political support to surmount remaining hurdles.