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High-resolution stratigraphic records through the Permian–Triassic boundary (PTB) interval of the global stratotype section and point (GSSP) at Meishan, Zhejiang Province, China reveal that the PTB crisis was not a single, abrupt catastrophe. A bed-by-bed analysis of environmental and biotic changes makes clear that the crisis can be resolved into two discrete episodes, each consisting of three stages: A) unstably oscillating conditions, B) peak crisis conditions, and C) ameliorating conditions. The first crisis episode commenced in Bed 23, peaked in Beds 24e–26, and ameliorated in Beds 27 and 28, while the second crisis episode commenced in Bed 29, peaked in Beds 34–38, and ameliorated in Beds 39 and higher. The macroscopic mass extinctions happened not at the beginning, nor the end of each cycle, but at times when the crisis or perturbation of environments began. These extinction events do not show …