This catalogue is the tenth volume of the SNG Turkey Project and covers the Ionian and Lydian coins in the collection of Yavuz Tatis, a businessman and collector living in Izmir (ancient Smyrna). Majority of the coins were acquired from 1993 when Tatis started to form his collection and continued until 2010. It is inferred from the information given by vendors that the provenance of the coins was western Asia Minor in general. The catalogue presents 931 coins dating from Archaic to Roman Imperial period and the most represented ones are from Smyrna, Ephesus, Colophon, Phocaea, Magnesia ad Maeandrum, Miletus and Clazomenae in Ionia and Sardis, Philadelphia, Thyateira, Hypaipa and Magnesia ad Sipylum in Lydia. The unidentified coins are grouped under the title of "Uncertain Western Asia Minor" at the end of the catalogue. During the preparation of the catalogue, Arif Yaci, one of Tekin's doctoral students, helped from the beginning; he took the photographs of the coins and revised the catalogue as well. Besides, Michel Amandry, Sencan Altinoluk and Aliye Erol-Ozdizbay also revised the catalogue before going into press. Monograms were drawn by Armagan Tan, one of Tekin's Master's students.