Contributions of this volume may be summarized into three aspects. First, Permian and Triassic regional stratigraphy of Tethys and western Circum-Pacific, especially of areas so far insufficiently known, or areas with remarkable progress recently, are extensively reported. Second, based on these data new views of Tethys in Pangea time, different from the popular patten given by Scotese and McKerrow, are suggested. To synthesize Permian-Triassic and test new views of Pangea and Tethys, data of so far less reported areas and facies are required, such as the Middle East and deep sea facies. Thirdly, besides comprehensive indication and interpretation, researches of the biotic alteration and causative global changes at the Permian-Triassic transition are now being carried out concurrently taxis by taxis, which has revealed that the procedure was multi-phasic, more variable and irregular than previously thought. This turning point of geological history is an interval of worldwide events happened in causality like a string of time-bombs, which provides excellent material for high resolution subdivision and correlation. We need cooperation among researchers such as under new IGCP projects to press onward along these directions, to achieve a better understanding of Permian-Triassic stratigraphic framework, environmental change and resource distribution, so as to serve the society and to enlighten the effort of mankind on sustainable development. © 2000 Elsevier B.V. All rights reserved.