Plans to change the rules on organ donation have moved a step closer following the publication of a Bill to create the UK's first opt-out system.
The Welsh Government says the Bill - which it hopes will become law by the summer - will increase organs available for transplant by a quarter.
It would mean everyone is considered to be a willing organ donor when they die, unless they have stated otherwise.
Evidence suggests such systems saw a 13-18% rise in donations.
But the government has warned there is no guarantee that legislation on its own will result in a higher rate of organ donation.
A total of 237 Welsh people are currently waiting for transplants.
Ministers tabled the Human Transplantation (Wales) Bill to introduce presumed consent in organ donation.
If passed by the Welsh assembly it could come into force by 2015.
The Welsh government stresses that doctors would not add to the distress of families by insisting on taking organs from deceased relatives, although families would not have a legal right to veto the process.
Another piece of research found the main reason families stopped organs being taken was because they did not know what their relatives' wishes were.
The Welsh government says changing the law would help "clarify" people's intentions.
Its campaign asks people to have a "heart to heart" with their loved ones about organ donation in the new year.
Health Minister Lesley Griffiths said: "The wishes of the deceased are paramount and the vast majority of the people of Wales do expect their wishes to be what really counts.
"For that reason, as is the case now, the family has no legal right to veto but, in practice, a clinician would never add to their distress by insisting on donation."
She added: "We know a soft opt-out system alone won't increase donation rates.
"Evidence from other countries shows the health service infrastructure has to be right to make it work."
Officials say they are confident the NHS has the capacity to cope with presumed consent.
They hope it will lead to 15 extra donors leaving around 45 more organs for transplant every year. As now, organs could go to recipients anywhere in the UK, not just in Wales.
Of around 250 potential donors last year, 67 actually left organs.
The presumed consent law would apply to over-18s who die in Wales if they have lived in Wales for more than six months.
People will still be able to sign up to the organ donor register so their wishes will be known if they die outside Wales.
After the law has been changed, ministers will have a duty to publicise the system.
Almost £8m will be spent over 10 years on the system.
There has been opposition to the changes from churches and from within the Muslim and Jewish communities.
The bill would involve transferring some powers from the UK government to Welsh ministers.
Conservative assembly members will have a free vote on the issue.
Conservative health spokesman Darren Millar AM said: "This remains an extremely emotive issue and thorough scrutiny of the bill's development continues to be important.
"There are lower rates of organ donation in some countries that have already implemented presumed consent so it's important that this scheme is not seen as the only way to increase donation rates."
Liberal Democrat AMs support the bill and the Plaid Cymru group is expected to do the same.
Delyth Lloyd of the British Heart Foundation in Wales welcomed the Welsh government's legislation.
"The shortage of suitable organs across the UK continues to cause unnecessary deaths and suffering, both to patients and their families waiting for that life-saving transplant...
"Wales is leading the way with this groundbreaking change in legislation. The rest of the UK should sit up, take notice and follow its lead."