This is the first of three volumes which offer a detailed analysis of one of the major city-blocks of ancient Pompeii, destroyed by the eruption of Vesuvius in AD 79. Excavated between 1926 and 1932, the Insula of Menander is so named after the structure that occupies over half the block'stotal area of 3,500 square metres, the House of the Menander, one of the grandest mansions of the city. Other, smaller houses, notably the House of the Lovers and the House of the Craftsmen, occupy outlying parts, and a number of shops and apartments are interspersed among them. The purpose of thepresent volume is to document a complete survey of the architecture of the block and thus trace the structural history of the Insula, with its intricate pattern of changing property-boundaries, over the 250-300 years of its existence. Subsequent volumes will examine the decorations (wall-paintingsand mosaic pavements) and the objects that were found during excavation. Paradoxically, while Pompeii is one of the best known of all Roman archaeological sites, very few areas of the site have been fully published. This is the first time a global study has been undertaken of one of the majorcity-blocks and it shows the enormous potential of such investigations to reveal insights into the social history of the city.