The cornerstone of international refugee law is the principle of non-refoulement , which protects refugees, asylum seekers, and other persons with protection needs from being returned against their will to a place where they risk facing persecution or other fundamental rights violations. A person who is protected against refoulement may, however, return voluntarily. Determining when such returns are truly voluntary is an issue increasingly at the heart of discussions about the lawfulness of returns, including recently in the Lake Chad Basin, East Africa, the Middle East, Southeast Asia, Europe, and Australia. Today, there does not appear to be a generally agreed legal standard to determine when a return is truly voluntary. Likewise, international law does not define a clear line at which State action to 'incentivize' or 'induce' returns amounts to refoulement or an unlawful expulsion. However, recent publications by international law expert bodies and ensuing debate among States have provided some indications as to where international law stands on the issue and the direction in which it might develop. Thus, this article first examines the interplay between voluntary returns and the principle of non-refoulement. Secondly, it analyses recent positions taken by the International Law Commission and the United Nations Committee against Torture concerning legal limits on the measures that States may take to incentivize or induce returns. Thirdly, the article considers certain measures taken by States to incentivize or induce the 'voluntary' return of a person and indicates when such measures may amount to acts of coercion or force in violation of international law. [ABSTRACT FROM AUTHOR]