The Arundell family of Lanherne, near Newquay, was one of the richest and most important in Cornwall in the late Middle Ages, having extensive property in most parts of the county as well as elsewhere (notably Devon and Dorset). Cornwall Record Office has recently acquired the family archive, and this provides the opportunity for publishing some of its rich contents. As a first offering, this volume contains rentals and surveys of the Arundell lands in Cornwall from the fourteenth to the sixteenth centuries. These documents list the lands and tenants of each property belonging to the family, often in considerable detail. The earliest survey is dated 1343, just before the Black Death, and covers some of the Arundell lands in the area of St Columb Major, Newquay and Padstow. The earliest full survey is for 1451-63 and includes those properties and others in the areas of the Lizard, Penwith, St Austell, Bodmin and the Clay Country. Even then the family lands were still growing, and in the sixteenth century are added further properties in South Cornwall (including one near Looe) and elsewhere; these appear in the later documents published here. These rentals and surveys provide much information about Cornish history in general and in particular for local and family historians in Cornwall, for those interested in social and agricultural history, manorial history, place-names and personal names. There is an introduction covering some of the topics illustrated by the surveys, and helping to make the material accessible to non-specialists.