The timing of this latest work in the impressive series of Concurrences projects could hardly have been more apt. 2020 was a bumper year, in both EU and national courts, for judgments involving judicial review of enforcement decisions in unilateral cases. At the same time, however, of the most significant unilateral cases pending before the General Court, three – Intel (on renvoi), Google (shopping) and Google (Android) are, at the time of writing, still in délibéré, with judgments expected later this year or next. Lawyers, economists and, above all, businesses at risk of being regarded as dominant, especially in the digital sector, will be looking to the judgments in these cases, each of which has its distinctive facts, to clarify the analytical framework for determining whether, and specifically why, unilateral conduct of a dominant undertaking crosses the – sometimes all too obscure – line into transgression. It, therefore, seemed to the Editors that, while waiting for these three judgments (and then, in all probability, the results of any appeals), many practitioners might find it useful to look back over recent years to see how the judicial review of decisions of competition authorities, both Commission and national (NCAs), has evolved.