The design and construction of earth and rockfill dams always result in a unique structure. Necessarily, dam engineering – like any other engineering discipline – has to follow basic rules which can be noticed in all structures as design criteria or as constructional peculiarities. Such criteria and peculiarities are discussed in this book. We will notice that the variety of natural construction materials and of potential dam locations demands that designers and builders show extreme scientific and practical effort. It is a challenge for flexibility and innovation.