Entry into force governed by reciprocal notification; treaty applies from the fiscal year beginning after entry. Entry into force is effected by reciprocal written notifications through diplomatic channels confirming each State's completion of internal procedures; the Agreement enters into force on the date of the later notification. The treaty's provisions apply prospectively: in India with respect to income for the fiscal year beginning after the calendar year of entry into force, and in Bhutan with respect to income for the year of income beginning after that calendar year.