The search for the earliest stone tools is a topic that has received much attention in studies on the archaeology of human origins. New evidence could position the oldest traces of stone tool-use before 3.39 Myr, substantially earlier than previously documented. Nonetheless, the first unmistakable evidence of tool-making dates to 2.6 Ma, the period in which Oldowan assemblages first appear in the East African record. However, this is not an unchangeable time boundary, and considerations about the tempo and modo of tool-making emergence have varied through time. This paper summarizes the history of research on the origins of stone knapping in Africa and places the current evidence in a historical perspective.