Sustainability metrics are significant in environmental policy as they provide quantifiable measures to assess progress towards sustainable development. These metrics enable policymakers to evaluate the effectiveness of various environmental initiatives and ensure that actions align with sustainability goals. They can include indicators related to waste management, resource consumption, and biodiversity conservation. By incorporating these metrics, governments and organizations can foster better decision-making, promote transparency, and engage stakeholders in achieving environmental objectives. Ultimately, this leads to policies that are more informed and responsive to both ecological and socio-economic challenges.