"The National Kidney Registry ("NKR") Voucher program allows donors to donate their kidney in advance (even years) before their intended recipient may need a kidney. Some Voucher donors have donated 20+ years before their intended recipient is expected to need a transplant with the hope that their intended recipient will never need a transplant. The Voucher program is a subset of the NKR Advanced Donation Program which began in 2011." Source: https://www.kidneyregistry.org/info/voucher-program.
Ned said that, in addition, sometimes a donor's work- or life-schedule makes scheduling a kidney donation difficult. And sometimes a donor's scheduling issues can affect a paired donation. Also, timing issues may arise when a donor wants to donate a kidney as part of a KTC to benefit an identified patient (such as a donor motivated by one individual's personal story) but cannot make herself available on the date that the KTC planners need her to donate in order to keep the chain going. In such circumstances, the NKR Advanced Donation Program might provide a solution.
With the Voucher Program, Ned said, the first donation in the KTC is by the donor at her convenience and schedule, thereby starting the KTC. That donor designates her intended beneficiary to receive a Voucher that becomes activated upon completion of her initiating donation. And the intended beneficiary gets priority to be the end transplant recipient in a KTC.
Ned spoke of such a situation in a 2017 KTC. Margaret donated in August and gave a voucher to Richard. Richard received his kidney 12 weeks later. Currently, DonorToDonor is working on another Voucher situation where the Voucher recipient is very difficult to match.
See the NKR's link discussing its Voucher program: https://www.kidneyregistry.org/info/voucher-program.