Families would have no legal right to stop dead relatives' organs being used for transplant if the person has not opted out in advance, under a proposed Welsh law.
However, Health Minister Lesley Griffiths said she could not see a situation where doctors took organs without the permission of families.
Ministers are asking for views on plans for a "soft opt-out".
If it goes ahead, Wales would be the UK's first country with the system.
Ms Griffiths said the lack of organs and tissues caused unnecessary deaths and suffering.