A District Collector-cum-District Magistrate (also known as Deputy Commissioner in some states) is an All India Service officer of the Indian Administrative Service (IAS) cadre who is responsible for land revenue collection, canal revenue collection and law & order maintenance of a District. District Collector (DC) cum District Magistrate (DM) come under the general supervision of divisional commissioners wherever the latter post exists. India has 748 districts as of 2021.