President Michael D Higgins said too many people die each year waiting for the transplantation of scarce organs.
The President paid tribute to the generosity of organ donors and their families for providing the greatest possible gift to others.
He stressed that, despite the sensitive nature of the issue, society must not avoid discussing the questions raised by organ donation.
“Some of those questions may be of a moral, ethical kind. Indeed, the technologies and practices of organ donation and transplant surgery have a profound influence on the ways we conceptualise the human body, how we relate body parts to the whole, to the person.
“And we must face all of these questions so that we are able to build magnificently on the generosity of donors and relatives”, President Higgins said.
He was speaking at the National Commemorative Garden for Organ Donors in Salthill, on Saturday.
The President had earlier joined more than 1,000 members of the organ donation community at the Irish Kidney Association's 29th Annual Service of Remembrance and Thanksgiving at Galway Cathedral.
It was the first occasion in almost 30 years for the service to be held outside of Dublin.
The annual service also marked the anniversary of the production of the ‘Book of Remembrance’ containing the names of organ and tissue donors and which has been an integral part of the service since its inception.
Members of Transplant Team Ireland, who last month participated in the European Transplant and Dialysis Sports Championships in Krakow, played a central part in the service.
President Higgins and his wife, Sabina, were guests of honour afterwards at a ceremony at the Circle of Life commemoration garden in Salthill.
In his address, the President paid tribute to Galway couple Martina and Denis Goggin who had initiated and completed the garden project following the death of their only child, Eamonn, in a car crash in July 2006.
The garden honours all organ donors, their families and recipients.
President Higgins described organ donation as an act “of incredible solidarity”.
He said: “While these donations are essential for the treatment of certain illnesses, and while transplantation is now a commonplace technique in Ireland, too many people die each year waiting for transplants that cannot take place because of the shortage of donated organs.
“This shortage of donated organs has also, of course, very great social and ethical implications when organs are illegally removed from the body for the purpose of commercial transaction, as sadly happens in parts of the world.
"The World Health Organisation has recently issued warnings of the scale of the contemporary global trade in body parts, of which the poor of the world are the primary victims."