Roman law is — together with Greek philosophy and Christian doctrine — one of the great legacies of the classical world. Without it, the entire history of Western civilisation would have been very different from what we know. Our aim has been to make English-speaking readers increasingly familiar with a significant shift that has characterised in recent decades the study of this crucial aspect of our past. A radical change of perspective that has placed at the centre of modern attention no longer only the Justinian's Corpus iuris civilis through which to reconstruct 'classical Roman law' as an organic totality out of time in its purity, but the figures of the single jurists and the contents of their writings in their specific historicity and in the context of the epoch to which they belonged: science and power; ideas and politics; successes and failures. It was in fact the jurists who, over at least three centuries of uninterrupted work, were the authentic creators of Roman law: as we can read in a lapidary statement by Ronald Syme. Our book is dedicated to four of the most important of them: Quintus Mucius Scaevola, Sextus Pomponius, Julius Paulus, Domitius Ulpianus, along with their thoughts, their lives, their intellectual strategies.