The task of philosophy, the French philosopher Gilles Deleuze once wrote, is to 'overturn Platonism'. This might be true, if only we could define what Platonism is. In this clear and accessible book Mauro Bonazzi provides the first comprehensive introduction to ancient Platonism. He begins his story with Plato's Academy before moving on to the sceptical turn which occurred during the Hellenistic centuries. He then explains the theologically oriented interpretation of Plato typical of Middle Platonists and concludes with the metaphysical systems of the Neoplatonists. Platonism has often been regarded as no more than a trivial repetition of the same doctrines. This book, however, demonstrates how the attempts of Platonists over the centuries to engage with Plato's thought constitute one of the most philosophically challenging moments in the history of ancient philosophy.