In a News and Views article appearing in the March 4 issue of Nature, Professor Markus Buehler and postdoctoral associate Zhiping Xu comment on a paper by Antonio Pons and Alain Karma that makes an important contribution to the study of a fracture mechanism found under mixed mode loading. In “Materials Science: Mind the Helical Crack,” Buehler and Xu say that the “cracking process is complex, and predicting the path a crack will take remains a challenge. Part of the difficulty is that cracking is a multiscale phenomenon — that is, it depends on mechanisms that operate across multiple length scales.” Buehler and Xu also review opportunities for future research in this area. Read the article in Nature.