Eradicating transplant tourism depends on complex solutions that include efforts to progress towards self-sufficiency in transplantation. Meanwhile, professionals and authorities are faced with medical, legal, and ethical problems raised by patients who return home after receiving an organ transplant abroad, particularly when the organ has been obtained through illegitimate means. In 2016, the Declaration of Istanbul Custodian Group convened an international, multidisciplinary workshop in Madrid, Spain, to address these challenges and provide recommendations for the management of these patients, which are presented in this paper. The core recommendations are grounded in the belief that principles of transparency, traceability, and continuity of care applied to patients who receive an organ domestically should also apply to patients who receive an organ abroad. Governments and professionals are urged to ensure that, upon return, patients are promptly referred to a transplant center for evaluation and care, not cover the costs of transplants resulting from organ or human trafficking, register standardized information at official registries on patients who travel for transplantation, promote international exchange of data for traceability, and develop a framework for the notification of identified or suspected cases of transnational transplant-related crimes by health professionals to law enforcement agencies.