Net foreign exchange requirement governs duty free imports and domestic sale entitlements for export units. Export oriented units under EOU/EHTP/STP/BTP schemes may import and procure goods and capital equipment duty free for authorised activities, subject to actual user conditions and applicable statutory permissions. Units must maintain positive Net Foreign Exchange (NFE) performance calculated over multi year blocks; NFE non compliance risks penal action and loss of benefits. A Letter of Permission/Letter of Intent, together with a legal undertaking, authorises operations; DTA sale entitlements are conditional on positive NFE and attract concessional or full duties as specified. Transfer, subcontracting, and exit require prior intimation, customs procedures, and settlement or security for duty liabilities.