This book consists of a series of studies of Codex Zacynthius (Cambridge, University Library MS Add. 10062), the earliest surviving New Testament commentary manuscript in catena format. A research project funded by the UK Arts and Humanities Research Council has produced new multispectral images of the palimpsest undertext in order to enable a thorough investigation of the manuscript and the creation of a complete electronic edition. This volume, co-authored by the members of the project, will provide a full account of the research undertaken by the project. Many advances have resulted from this research, which will be presented here for the first time in print.