Gustaf Linnarsson contributed in his short life to the solution of many thorny geological problems outwith his own country. In particular, his work as a biostratigrapher on the fossils and rocks of the Lower Palaeozoic of Sweden was used by H. Alleyne Nicholson of Aberdeen and Charles Lapworth of Birmingham to help solve the problems of correlation of the Lower Palaeozoic of Wales, Northern England and Scotland. It eventually enabled Lapworth to work out the Tripartite Classification of the Lower Palaeozoic. The close connection between these three geologists was particularly fruitful in resolving and promulgating the techniques of using zonal fossils, especially graptolites. There is considerable evidence of the close international co-operation here. Of special importance was the application of Linnarsson's findings to the dating of the Cambrian-Precambrian interface in the late nineteenth century. A final point of significance is the psychological and practical effect that such work and co-operation had on Charles Lapworth, then in the early stages of his geological career.