Advanced donation is kidney paired exchange separated in time; the Voucher Program is based on this. In the Voucher Program, the donor donates first, to a stranger. That donation then provides a voucher for the recipient, which can be redeemed when that recipient is ready for transplant. Voucher donation allows the donor to donate when they are ready, provided they are activated in the NKR system at least three weeks before their intended donation date. Voucher donors typically start a paired exchange chain, which helps other patients in need of a transplant.