The paleontological site of Dikika in the Afar Depression of Ethiopia (Figure 19.1) has been systematically studied since 1999, when a team led by one of us (ZA) launched the Dikika Research Project (DRP). This project set out to survey and document sedimentary exposures of the Hadar Formation south of the Awash River (Figures 19.2 and 19.3), and has produced important discoveries of fossil hominins and other mammals from the time between about 3.6 and 3.2 Ma. These discoveries include the earliest and most complete skeleton of an Australopithecus afarensis juvenile at locality DIK-1 (Alemseged et al., 2006); the earliest hominin from the Hadar Formation at locality DIK-2 (Alemseged et al., 2005); a new species of Canidae, Nyctereutes lockwoodi (Geraads et al., 2010b); a new species of gigantic otter, Enhydriodon dikikae (Geraads et al., 2011); and a new species similar to some modern otters, Lutra hearsti (Geraads et al., 2015b). Also, the earliest traces of stone-tool-modified bones were described from locality DIK-55 (McPherron et al., 2010). The study of these fossils and their paleoenvironmental context has offered new perspectives on the evolutionary forces that may have shaped early hominin adaptations (Wynn et al., 2006). The Dikika Research Project has therefore played a key role in deepening our understanding of A. afarensis paleobiology and its environmental context during the Pliocene.