To have increased tool life and wear resistance, multicoated carbide inserts with a hard metal substrate have been recently developed. Widalon is one such insert, having multiple coatings of TiC, Ti (C, N), TiN and AlON. Widalon was first introduced on the Indian market by Widia (India) Ltd. around 1985 but little work has been done to determine its full potential. In this paper some investigations have been made on the wear mechanisms while machining En24 (817 M 40) steel. It has been observed that the AlON coatings provide the best crater wear resistance under high speed cutting conditions. It is the flank wear which determines the tool life. Grooving wear, in contrast, is quite insignificant under the conditions investigated.