Human rights organisations have warned repeatedly that basic human rights are being challenged in the so-called 'War on Terror'. One particularly controversial area is the use of diplomatic assurances against torture. According to international human rights instruments, the state shall not return anyone to countries in which they face a substantial risk of being subjected to torture. In the 'War on Terror', an increasing number of non-citizens are being deemed 'security threats', rendering them exempt from protection in many Western states. To be able to deport such 'threats' without compromising their duties under international law, states are increasingly willing to accept a diplomatic assurance against torture – that is, a promise from the state of return that it will not subject the returnee to torture. There is wide disagreement as to whether and/or when diplomatic assurances can render sufficient protection to satisfy the obligations of non-refoulement to risk of torture. Whereas the human rights society label such assurances as 'empty promises', others view them as effective, allowing states to retain their right to remove non-citizens without violating international law. This article reviews international and selected national jurisprudence on the topic of diplomatic assurances against torture and examines if and/or when such assurances might render sufficient protection against torture to enable removals in accordance with international law. The courts and committees that have reviewed the use of diplomatic assurances against torture have identified essential problems of using them, thus rejecting reliance on simple promises not to torture. However, they have often implied that sufficient protection might be rendered by developing the assurances. I argue that this approach risks leading the governments into trying to perfect a system that is inherently flawed – whilst, incidentally, deportations to actual risk of torture continue. Even carefully modelled assurances render only unreliable protection against torture. For this, and reasons connected to undesirable side-effects of their use, I argue that the practice should be rejected.