This text aims to provide an insight into all the major stages in the life of an oil or gas field; from exploration, through appraisal, development planning, production, and finally to decommissioning. With a comprehensive introduction to the upstream industry; useful for industry professionals who wish to be better informed about the basic methods, concepts and technology used. It is also intended for readers not directly working in oil and gas companies but who are providing related support services. This volume should help the reader to understand the major technical and business considerations which make up each part of the life of a typical oil or gas field, and to demonstrate the link between the many disciplines involved.