Anthony Clark has written the first general survey of an increasingly important area of practical archaeology. The emphasis is on the principles and practical application of the well established techniques of resistivity, magnetometry and magnetic susceptibility, with shorter sections on emerging and less common techniques such as ground-penetrating radar, electromagnetic methods and phosphate survey. This paperback edition updates and enhances the earlier book, adding new material such as the large-scale evaluation exercises now required as a precondition of planning consent for major developments.