Recycling of oceanic plate back into the Earth's interior at subduction zones is one of the key processes in Earth evolution. Volcanic arcs, which form above subduction zones, are the most visible manifestations of plate tectonics, the convection mechanism by which the Earth loses excess heat. They are probably also the main location where new continental crust is formed, the so-called `subduction factory'. This volume contains a collection of papers that exploit the relative simplicity of intra-oceanic subduction systems to provide insights into the tectonic, magmatic and hydrothermal processes associated with subduction.