This article marks the twenty-fifth anniversary of Global Environmental Politics (GEP) by conducting an extensive review of the scholarship on long-term global environmental policy, with a particular focus on climate change. Drawing on articles published in GEP and twenty political science and interdisciplinary journals, we identify three key research themes: the persistent problem of time inconsistency and credible commitment, the rapid rise of net-zero targets and long-term low emissions development strategies, and a shift from analyzing climate mitigation as an international collective action problem toward framing it as a distributive-conflict problem within domestic economies. Building on these themes, we outline four open research challenges for the long-term environmental policy community—ranging from assessing long-term targets and policy instrument mixes to designing intergenerational compensation schemes—that may guide future research and improve the practical design of credible climate and environmental policy.