The Isle of Man lies close to the surface trace of one of the most important regional Palaeozoic structures - the Iapetus Suture. Evidence suggests that this boundary, between the former Avalonian microcontinent to the south and the Laurentian continent to the north, skirts the northwestern edge of the island. Over most of the British Isles the surface trace of the suture is hidden by Upper Palaeozoic rocks. However, on the Isle of Man, where Lower Palaeozoic rocks crop out at the suture, research promises to substationally augment our knowledge of the geology of the Iapetus Suture Zone and of the outboard edge of the Avalonian margin. As well as providing an overview of a key Caledonide area adjacent to the Iapetus Suture, the papers in this volume describe new work on stratigraphy, sedimentology, deformation, metamorphism, geochemistry, plutonism, palaeomagnetism and geophysics. There are descriptions and an analysis of a range of deep-water sedimentary processes on an early Ordovician continental margin and a detailed analysis of the processes occurring in the developing collision zone between Avalonia and Laurentia. Review papers cover the analogous rocks of Eastern Ireland, the Scottish Southern Uplands and the English Lake District. In Sight of the Suture is the first overview of the pre-Carbonisferous geology of the Isle of Man since the 1960s. It will be of prime interest to research workers in the geology of the Caledonian/Appalachian orogenic belt, to sedimentologists interested in deep marine processes and to petroleum geologists focusing on exploration in the Irish Sea.