Second, if the VCLT provides that the agreements are binding on the parties and must be implemented in good faith (Article 26 VCLT), not all provisions of a contract necessarily lead to a legal obligation whose breach results in non-compliance. Contracts often contain a mixture of mandatory and storage items. For example, the emissions target set by Article 4.2 of the United Nations Framework Convention on Climate Change has been designated as an “objective.” Although the Paris Agreement will be a treaty, it is not necessary for all elements of the agreement to be legally binding on the parties. For example, countries` “national contributions” (NDCs) – that is, their emission reduction targets – could take the form of a political objective rather than a legal obligation. Keywords: climate change, treaties, Paris agreements, UNFCCC, legal form, hard law, soft law Finally, most people, including President Hollande, think that the Paris agreement will be more effective if the NSCs of countries are legally binding, this is not necessarily the case. The effectiveness of an international regime depends on three factors: (1) the objective of its commitments; (2) the amount of state participation; and (3) the degree to which states comply with the rules. Those who argue for the importance of a legally binding result in Paris focus above all on compliance. But the legally binding nature of the party NDCs could also have a negative impact on ambitions and participation. While the legally binding nature of a provision improves compliance – a plausible assumption, but one that has opposed empirical evidence – other factors may also promote compliance, including transparency and accountability mechanisms that make it more likely that poor performance will be identified and criticized, increasing reputational costs for the state concerned. Unlike President Hollande, these review procedures do not depend on the legal character of the parties` NDCs; Non-binding provisions can also be subject to a strong monitoring, reporting and verification system. The question, therefore, is to what extent the additional compliance would result from the application of the legally binding CNN and whether this added value could be offset by a reduction in participation and/or ambition.