Scientist David Goodall, 104, has died after choosing to end his life at a clinic in Switzerland, a right-to-die organisation says.
The lauded ecologist and botanist, who was not terminally ill, said the decision had been driven by his diminishing independence.
Mr Goodall had flown from Australia for his assisted suicide, attracting the attention of people around the world.
In his final public appearance, he said the public interest had surprised him.
Mr Goodall died peacefully at 12:30 (10:30 GMT) in Basel, Exit International said.
In an interview on his birthday last month, he said: “I’m not happy. I want to die. It’s not sad particularly. What is sad is if one is prevented.”