ROSEMARY Stewart, who has died aged 90, was an Oxford academic who for five decades exhaustively studied what makes a good boss.

Her research focused on the practices of managers across different jobs, and what made the best leaders, and particularly the practises of the NHS in England and Wales.

Dr Stewart was one of the first fellows of the Oxford Centre for Management Studies, now part of Green Templeton College, having joined shortly after it was founded.

When she retired in 1992 she became Templeton College’s first emeritus fellow, and later an honorary fellow when it merged with Green College in 2008.

In a tribute to Dr Stewart, the college said she had “shaped the development of the discipline of management studies at Oxford University”.

One of her former students and recipients of a scholarship she funded, Tomas Farchi, said: “Her knowledge, passion, and lasting academic interest on managerial work and behaviour in the NHS were instrumental for my understanding, as a foreigner, of the history and evolution of one of the most fascinating health care systems in the world.

“Rosemary´s collegiality, intellectual commitment, and generous support are lasting examples and a source of gratitude.”

She was born in London on December 20, 1924, to parents Sylvia and and William, an investor and former air force pilot.

The family moved to Pulborough in Sussex during the economic depression and she was educated at a private school in Worthing, West Sussex.

After the first year, her mother took her to Saskatoon, in Canada, where they had relatives and she graduated from a high school there.

Her mother then returned to England and Rosemary went to Vancouver, spending a year doing secretarial work at a real estate agency before her talent impressed an American visitor whose father was the president of the University of British Columbia in Vancouver. She graduated in economics from the university, and after the war’s end in 1945 returned to England.

She went on to study social philosophy at the London School of Economics, later doing her doctorate in management studies. In 1956 she became a researcher for what was then a small independent research society, the Acton Society Trust, specialising in the problems of large organisations and accountability in newly nationalised industries.

Dr Stewart later rose to director in the society, working with pioneering social scientists such as Tom Burns and Joan Woodward.

In 1961 she married Ioan Mackenzie James, an Oxford mathematics don, and fellow of St John’s College.

They settled down in Blackhall Road, in Oxford, near St John’s.

In 1966 she became the first female fellow in organisational behaviour at the Oxford Centre for Management Studies, based in Kennington, at what is now Egrove Park from 1968.

At this time she and her husband moved to Drake House, in Hinksey Hill, a home they shared until her death.

From 1977 to 1978 she was a senior tutor at the Oxford Centre for Management Studies, and dean from 1983 to 1985.

She became director of the Oxford Health Care Management Institute when it was founded in 1996.

Dr Stewart’s main interest was management in the NHS.

She ran workshops for many years for NHS chief executives, also lecturing on the subject in many parts of the world, and was widely known for her extensive writings on managerial work and behaviour.

A detail-heavy approach saw her use structured interviews, diaries, observations, group discussions, case analysis, and critical incidents.

Her 17 books included Contracts for Management, Choices for the Manager, The Reality of Organisations and most famously The Reality of Management.

Dr Stewart was also vice-chairman of the Oxfordshire Family Health Services Authority and a director of the Centre for Development and Population Activities, based in Washington DC.

Uppsala University in Sweden awarded her an honorary degree and, in 2008, she was promoted to membership of the Royal Society of Medicine, an unusual achievement for a non-medic.

Her hobbies outside academia included music and opera.

Dr Stewart died on June 15. A funeral was held at Oxford Crematorium on June 26.

She is survived by her husband. They had no children.