This fifth edition of Rock Slope Engineering has been prepared 42 years after the first edition authored by Evert Hoek and John Bray in 1974, and 12 years after the fourth edition in 2004. This 42-year period is an expression of the evolution of this field of engineering – the first three editions, published by the Institute of Mining and Metallurgy in London, were prepared for the design of open-pit mines that were at that time becoming several hundred metres deep as the result of the development of drills, shovels and trucks that made it economically feasible to mine low-grade ore deposits. Open-pit mines are now reaching depths of 1000 metres and new procedures are being used to design slopes for these pits for which the rock mass strength is more important than the geologic structure. These procedures are documented in publications such as the Guidelines for Open Pit Slope Design (2009). <...>