Dr Elizabeth Wilson was the founder of Glasgow-based pro-euthanasia group Friends at the End (FATE).
In 2009 she was arrested by Surrey Police on suspicion of giving advice on suicide to multiple sclerosis sufferer Cari Loder – who killed herself using a helium cylinder and a hood.
The arrest was the first carried out under new laws for assisted suicide in England and Wales – and saw Wilson facing up to 14 years in prison until it emerged she was not to be prosecuted.
But in the years that followed she continued to give advice to those planning to end their own lives - including two Scots who travelled to Switzerland to kill themselves in 2014.
Now the 89 year-old has died in her home - after refusing treatment for pancreatic cancer.
Dr Wilson was diagnosed with the disease several weeks ago, but refused palliative treatment for the disease.
She is said to have died peacefully at her home in Glasgow’s West End with her family at her side.
Sheila Duffy, convener of FATE said: “She was a doughty fighter for the rights of the individual, but more importantly a warm, friendly, courageous woman who simply loved people and cared what happened to them at the beginning and the end of their life.”
Surrey-born Dr Elizabeth Wilson – known as “Libby” to friends – arrived in Glasgow in 1967 after her husband was offered a position as professor of medicine at Glasgow University.
She practiced as a doctor in the city throughout the 1960s and 70s, working primarily in family planning clinics.
But after her retirement her campaigning for the legalisation of suicide began after she was asked along to a meeting of the Scottish Voluntary Euthanasia Society.
In 2000 she became a founding member of FATE - and worked with the late independent MSP Margo MacDonald on the failed bid to give the terminally ill the right to assisted suicide.
In 2014 she advised Stuart Henderson, 86, and his cousin Phyllis McConachie, 89, from Troon on their bid to take their own lives.
Neither of the pair were terminally ill, but they had relied on each other in a sheltered housing complex for 40 years.
They took their lives using lethal medication at the Eternal Spirit in Basel, Switzerland.