The first edition of Rock Mechanics and Engineering bridged the gap between scientific research on rock mechanics and practical engineering. It was resolutely aimed at giving practical information to geologists, engineering geologists and engineers. Emphasis was placed on the lessons to be learnt from the study of case histories, with the Malpasset Dam rupture and the large Vajont rock slide amongst those described. In this second, enlarged edition the author continues to emphasise aspects of rock mechanics. Modern efforts at establishing an engineering classification of rocks are summarised and considerable attention is given to the Austrian tunnelling method. Firm in his belief that there is no better way to study the subject than by the detailed analysis of case histories, Dr Jaeger has incorporated a number of new ones, for example the discussion on the engineering classification of jointed rock masses and the required rock support is illustrated by descriptions of the second Gotthard Tunnel and the design of the third, much larger tunnel.