William Duff went to Dubai after a stint as a banker in Kuwait and became financial advisor to the late Sheikh Rashid bin Saeed al Maktoum in 1960.
At the time, the emirate's population was about 50,000; it survived largely on fishing, herding and small-scale trade across the Gulf in wooden dhows.
Mr Duff set up the Dubai Customs Department and Department of Finance, helped to establish the emirate's electricity utility, and was later instrumental in creating the Jebel Ali Free Zone.
The emirate is now the region's top financial centre, with a population of more than two million.
An Oxford-educated Arabist and classical Arabic speaker, Mr Duff navigated the inner circle of the ruling family in the days when his employer and other senior royals spoke little English.
"He went to meet Sheikh Rashid, and they got on straight away. They used to enjoy going on trips to Scotland together. It was more than a business relationship - it was a friendship as well," said Mr Duff's daughter, Sheila Duff-Earles.
"He was an excellent father. He was a fair man. He totally dedicated his life to working with the Arabs here — he treated Arabs as if they were his family," she added.
Anthony Harris, ex-British ambassador to the United Arab Emirates, said: "He really played a key role in the growth of the UAE. The drive was all Sheikh Rashid. But around Sheikh Rashid were these loyal servants, loyal in the sense that whatever ideas were outlined, they made it happen."
"He was very committed to Dubai and very much a significant part of the growth of the emirate in the sixties, seventies and eighties," said Francis Matthew, Editor-at-Large of Gulf News. "He was very straightforward, very honourable, and very transparent."
Mr Duff retired in Dubai and will be buried there this week. He is survived by his wife, Irenka, two daughters, Diana and Sheila, and four grandchildren.