Sixty-five years have passed since the publication of Basil Luyet’s Life and Death at Low Temperature , the first organized attempt to summarize past observations of freezing injury in living organisms and to infer from them the mechanisms of injury. Not surprisingly, attention at that time was focused primarily on mechanical damage from ice, although, as evidence of the immaturity of the science, Luyet considered five other possible mechanisms: the withdrawal of energy, attainment of a minimal temperature, too-rapid thawing, dehydration, and “various physiological, physical, or chemical alterations.” One might have expected that the subsequent years would have led to a clear and functional understanding of freezing injury and, as a result, have enabled efficient cryopreservation of almost anything. But it wasn’t that easy.