Recently, continental-scale geochemical surveys of Europe and Australia were completed. Thanks to having exchanged internal project standards prior to analysing the samples, we can demonstrate direct comparability between these datasets for 10 major oxides (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2 and TiO2), 16 total trace elements (As, Ba, Ce, Co, Cr, Ga, Nb, Ni, Pb, Rb, Sr, Th, V, Y, Zn and Zr), 14 aqua regia extracted elements (Ag, As, Bi, Cd, Ce, Co, Cs, Cu, Fe, La, Li, Mn, Mo and Pb), Loss On Ignition (LOI) and pH. By comparing these new datasets to one another, we can learn lessons about continental-scale controls on soil geochemistry and about critical requirements for global geochemical mapping. Although the median soil compositions of both continents are overall quite similar, the Australian median values are systematically lower, except for SiO2 and Zr. This reflects the generally longer and, locally more intense weathering in Australia (median Chemical Index of Alteration values are 72 and 60% for Australia and Europe, respectively). We found that element concentrations typically span 3 (and up to 5) orders of magnitude on each continent. The comparison of 2 continental geochemical surveys shows that the most critical requirement for global geochemical mapping is good analytical quality. Only where a comprehensive quality control program, including field and laboratory duplicates, internal project standards and Certified Reference Materials, is implemented and documented, are the results credible and comparable with other datasets.