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A re-appraisal of the Mesozoic and Cenozoic evolution of the Atlantic margin basins has been integrated with new data on source-rock kinetics, oil-source geochemistry and fluid inclusion studies to calibrate the petroleum systems of the study area and model these systems utilizing 2D modelling software.The high β factors that are reported from these basins are cumulative estimates. Superposition of rifting events and evidence of prolonged rifting until the early Paleocene demonstrate that heat flow patterns associated with a ‘cool’ rift model are most appropriate.New kinetic models for ‘Kimmeridge Clay’ and Middle Jurassic source-rock samples from released wells and BGS shallow boreholes allow more precise maturation modelling. Prolific oil-prone, Type I and Type I/II Middle Jurassic source rocks, together with fast-reacting Type IIS Upper Jurassic–Lower Cretaceous source rocks have been identified and indicate the range of kinetic models that must be considered during sensitivity analysis.In the Faeroe–Shetland area, complex mixing of both ‘fresh’ and biodegraded oils from different source rocks as well as different facies of the same source-rock formation are recognized. Gas chromatography–mass spectrometry (GC–MS) and compound specific isotope analysis (CSIA) of oil samples and petroleum fluid inclusions are used to differentiate between oil families and also to separate oils within a sample.A number of regional seismic sections were utilized for 2D modelling which was calibrated from well or pseudo-well models and incorporated new heat flow and kinetic data. These results and regional mapping indicate that the respective location of Lower Tertiary versus Upper Cretaceous depocentres is critical in determining the timing of maturation. Peak oil maturation occurs from mid Cretaceous to the present-day. Migration pathways initially focus hydrocarbons to Mesozoic (or older) highs. Early Tertiary faulting, mid Tertiary uplift and gas flushing then control re-distribution of hydrocarbons.