The Global Pact for the Environment (GPE) is a draft treaty prepared in 2017 by a French think tank, Le Club des Juristes, which aims at strengthening the effectiveness of international environmental law (IEL) by combining its most fundamental principles into a single overarching, legally binding instrument. In May 2018, the United Nations General Assembly (UNGA) adopted Towards a Global Pact for the Environment, a resolution that established an intergovernmental working group to discuss the necessity and feasibility of adopting an instrument such as the GPE, with a view to making recommendations to the UNGA. As the working group nears its final session, scheduled for May 20–22, 2019, this paper discusses the extent to which codifying the fundamental principles of IEL into a treaty could increase the problem-solving effectiveness of environmental governance. The analysis suggests that the added value of the proposed GPE (or any such instrument) may not be as evident as what its proponents argue. The paper also highlights the fact that the adoption of such an instrument could generate unintended consequences that would hinder the development of more effective environmental standards in the future.