Geotechnical instrumentation is used for installation, monitoring and assessment on any sizeable project, particularly in urban areas, and is used for recording, controlled remedial work, and safety. This unique and up-to-date book deals with the conceptual philosophy behind the use of instruments, and then systematically covers their practical use. It is divided into displacement dominated systems and stress recording systems. The limitations are discussed and the theoretical background for data assessment and presentation are covered in some detail, with some relevant background material in theoretical soil mechanics. Relevant advanced electronic techniques such as laser scanning in surveying and fibre-optics are also included and communication and data recovery systems are discussed. It is written for senior designers, consulting engineers and major contractors who need a major introduction to the general purpose, availability and analysis of field instruments before details of their own project can be progressed, and serves as a text book to any specialist geotechnical MSc or professional seminar course in which instrumentation forms a major part.