The poems of Catullus barely managed to survive the Middle Ages. All surviving copies of the collection derive from an extremely corrupt manuscript, and scholars have been working since the Renaissance to reconstruct the original text. This volume aims to contribute to this effort with a substantive Introduction, and with six original papers, from a team of noted international specialists. The papers were presented in 2011 at the conference 'What Catullus Wrote' at the Ludwig-Maximilians-Universitat, Munich. The authors represent different generations of scholarship and of academic tradition. They here study aspects of the manuscript tradition of the poems and their editorial history as well as contributing directly to the reconstruction of the text. The volume aims to set an example of a collaborative approach to textual criticism, in which significant choices are based not on the judgement of a single authoritative editor, but on the outcome of debate between scholars who represent a broad range of viewpoints.