The mosaics in the Rotunda in Thessaloniki are the most significant decorations that remain from the early Byzantine period. This richly illustrated book invites the reader to enter the building and experience the splendid golden and silver mosaics that cover cupola and vaults. After an introduction to the architecture of the Rotunda, the authors focus on the mosaics, discussing such issues as imperial patronage, the martyr portraits, the pictorial programme, as well as mosaic technique and the aesthetic qualities of the multi-coloured images. The succinct text provides an up-to-date introduction to the mosaics. It includes a timeline and a list of recent publications. Colour photos, many specially taken for this publication, document the spectacular qualities of these magnificent mosaics.