Field-based studies, be they regional or basin-scale fieldwork, or the examination of outcrop analogues, have been an important component of petroleum system studies in the upstream oil and gas industry for many years. Recent technological advances, founded on traditional field methodologies, whether they are in digital outcrop characterization or developments in processing and computational capabilities, have fuelled a resurgence in such fieldwork. These studies enable the building of realistic models that allow the exploration or production geoscientist to navigate effectively from plate-to-play-to-pore. The interrogation of field data and resulting models provide a more informed means of benchmarking the subsurface, as well as a more realistic view of subsurface uncertainty and the management of associated risk in subsurface description and prediction. This Special Publication records 12 papers given at a conference titled 'Reducing Subsurface Uncertainty and Risk Through Field-Based Studies' organized by the Petroleum Group of the Geological Society of London, and held in London from 4 to 6 March 2014. The observations drawn in this introductory paper reflect the authors' experiences, presentations at the conference and manuscripts within this volume.