Supply under GST defines taxable events and the elements determining when goods or services attract tax. The GST taxable event is the supply of goods or services for consideration in the course or furtherance of business. Supply includes sale, transfer, barter, exchange, licence, rental, lease, disposal and import of services, with specified transactions without consideration captured by Schedule I. Constituent elements are supply of goods or services, consideration (with exceptions), course or furtherance of business, taxability, and a taxable person; specified circumstances treat transactions as supply even if elements are absent.