An expert in motor industry economics, Prof Garel Rhys, has died aged 76.
Prof Rhys, who was raised in the Swansea valley and lived in Cardiff, died in his sleep at his home on Tuesday, one week before his 77th birthday.
He is survived by his wife and three children.
Tim Williams from the Welsh Automotive Forum said: "He was a great ambassador, fantastic academic, well respected, funny. He will be sorely missed."
Prof Rhys was the chairman of the Welsh Automotive Forum, professor emeritus and president of the Centre of Automotive Industry Research at Cardiff University and an adviser to the Welsh Government on economic and automotive affairs.
Mr Williams said: "Garel's death has been a tremendous shock to all in the forum and I know the sadness will be shared throughout the automotive community as we extend our very deepest and sincere condolences to his family.
"He was a wise counsellor, often taking an alternative view to the popular train of thought on an issue, but he was invariably right in the end.
"With his encyclopaedic knowledge of the Welsh automotive industry from the dawn of the motor car to the present day, I think it is fair to say we will not see his like again and he will be sorely missed by hundreds if not thousands whose lives he touched during a very full life."