The Acceptance of Necessity (AoN) is a critical concept and the foundational first step in India's defence capital acquisition process. It refers to the official approval granted for a specific proposal to procure military equipment or weapon systems for the armed forces. The mechanism is overseen by the Defence Acquisition Council (DAC), which was formed in 2001 following the recommendations on reforming the National Security System after the Kargil War. The DAC, chaired by the Defence Minister, is the apex decision-making body for defence procurement.
The AoN signifies the formal acceptance of the requirement for the proposed acquisition and is mandatory before any tendering or contracting process can begin. Once granted, the AoN fixes the categorization of the procurement, determining the procedural route the case will follow under the governing framework. This framework is the Defence Acquisition Procedure (DAP), which was most recently updated as DAP 2020. The DAP 2020 was promulgated on September 28, 2020, by Defence Minister Rajnath Singh, superseding the previous Defence Procurement Procedure (DPP) 2016.
The recent change in the procedure was explicitly drafted to operationalise the Atmanirbhar Bharat (self-reliant India) policy announced in May 2020. The AoN process now strongly connects to the 'Buy (Indian)' and 'Buy (Indian-IDDM)' categories, which mandate a preference for indigenously designed, developed, and manufactured equipment. While the AoN remains the initial gate, the subsequent procedure now prioritizes indigenous sources, with recent approvals accounting for 99% of the total value under these categories. This concept is distinct from the broader Doctrine of Necessity, which is a legal defense under criminal law, historically found in Section 81 of the Indian Penal Code, 1860, and now in Section 19 of the Bharatiya Nyaya Sanhita (BNS), 2023.