The basic objective of power sector reform in India has been twofold: provide electricity at an affordable price, and improve the quality of supply. Availability-based tariff (ABT), as an economic instrument, has successfully addressed both the issues: rationalise the tariff structure and ensure quality supply at the grid-level by defining a playing rule for both the generators and the beneficiary states. ABT has also been successful in devising an incentive system to arrest grid indiscipline.