This monograph presents the state of art of the geologic knowledge about the Spanish coast obtained through scientific research in the last 30 years. From a general point of view, coasts are the most quickly changing systems of the Earth. This is critical, since many human resources, such as the main part of economic and social activities, are located in the coastal areas. Especially in the case of Spain these coasts include cities, wide industrial areas (including harbor complexes), important ecologic systems, and our main economic resource: tourism. Understanding the dynamic functioning of each element of this coast is vital for correct future coastal management, so as to solve problems derived from bad plans developed in the last decades of the twentieth century. This is a valuable text for advanced graduate students and coastal researchers, which connects the specific dynamic functioning of the main Spanish coastal environments and their relationships with human activities.