Exchange of obsidian from a limited number of sources to most archaeological sites in the Middle East can be documented from the early Neolithic through the Bronze Age. Thus, precise provenance determinations for obsidian artifacts can provide important information conceming contacts among regions. Three regions, each with several discrete sources, have been identified as major suppliers of obsidian: Central Anatolia, the Greek Islands, and the Eastern Turkish-Soviet Armenian region. The analysis, by instrumental neutron activation, of samples from three sources in this region and four sources in the Central Anatolian region are reported. The source data are compared with the analyses of artifacts from the important highland Iranian sites of Tal-e Malyan and Tepe Yahya. The methods of provenance identification and the implications for exchange in obsidian at these two sites are discussed. See AATA 21-1449 for reference to entire book.