Recent investigation of the geochemical provenance of obsidian artefacts from spatially and temporally variable archaeological sites in Ethiopia has shown the diversity of geological sources and concomitant differences in the transport of raw material to archaeological sites, thus allowing reconstruction of the utilization of raw material by early hominids as well as recent humans. We recognize 30 compositionally different obsidians that were used at the Middle Stone Age (MSA) archaeological sites of Aduma (A8), Halibee Herto, Aladi Springs and Porc Epic in the Middle Awash region. Probable sources of nine of these obsidians are Adokoma, Ayelu, Ida'ale, Assebot, Asboli, Gira‐Ale and Kone. Many compositional types are confined to a single site, but others are shared between sites, although shared obsidians between sites more than 300 km apart are exceptional.