 Almheiri et al. (2013) have recently claimed that black hole complementarity is not viable on different, more physically oriented grounds. They argue that the following three statements, assumed by black-hole complementarity, cannot all be true: (i) Hawking radiation is in a pure state; (ii) the information carried by the radiation is emitted from the region near the horizon, with low energy effective field theory (i.e., the standard semi-classical approximation) valid beyond some microscopic distance from the horizon; and (iii) the infalling observer encounters nothing unusual at the horizon. Based on powerful grounds for believing the first two propositions, they conclude that the appropriate response to the paradox is to posit that there is a “firewall” at the event horizon: the flux of Hawking radiation from the black hole becomes in general so intense that highly accelerated infalling bodies are themselves incinerated as soon as they enter the black hole. This proposal is too recent for any consensus to have been reached about its viability; vigorous debate about it is ongoing. 