The very early development and extent of the obsidian trade in the Near East is being increasingly documented by the discovery and excavation of Early Neolithic sites throughout the area. Since the publication of our last paper (Renfrew, Cann and Dixon, 1966), obsidians from five aceramic Neolithic sites have been analysed, and the natural source of the material determined in each case. All the results fall into the framework of groups already established. In addition, one new obsidian source has been discovered.This confirmation of the characterizations hitherto achieved is satisfactory, but perhaps more important is the new evidence for the reconstruction of the pattern of the trade or traffic in obsidian in Early Neolithic times. Regularities in this pattern are becoming apparent, which allow a greater insight into the trading mechanisms involved.In this paper, written by Colin Renfrew on the basis of analyses and group divisions by J. E. Dixon and J. R. Cann, new information concerning the Anatolian sources is first considered, and new results for the Early Neolithic and later obsidians discussed. In the last section, an attempt is made at the more precise definition of the obsidian trading pattern in the 7th and 6th millennia B.C. on the basis of a more detailed analysis of the prehistoric trade statistics.