Her best known book, The Theory of the Growth of the Firm, published in 1959, brought her instant recognition as a creative thinker, and its importance to the analysis of the job of management has been increasingly realised. Earlier, she had published in 1951 a study of the economics of the international patents system. In 1968 she produced a book on the international petroleum industry, following it with a collection of essays in 1971. Her last book, written with her husband, was on Iraq in 1978.
Edith Tilton was born in Los Angeles in 1914 and began her university education there, marrying in 1934 at the age of 19 the surveyor of Californian Highway No 1, David Denhardt, who died four years later, leaving her with a baby son (now Professor of Chemistry of Rutgers College). By that time she had moved to Baltimore, to take her MA and PhD under the supervision of Fritz Machlup at Johns Hopkins University, writing a thesis on the growth of the Hercules Powder Company that formed the basis for her later work on the growth of the firm.
At John Hopkins she met Ernest Penrose, who held a chair in Economics and whom she eventually married in 1944 after working alongside him in Geneva and Toronto in the International Labour Office from 1939 to 1941. She also accompanied him to London where he was special adviser to John Winant, the US Ambassador, while she was appointed Special Assistant to him. From her second marriage she had three sons and enjoyed 40 years of happy married life before Pen's death in 1984.
She had returned with her husband to Johns Hopkins in 1950 and was based there for the next 10 years. But after a campaign they conducted in support of Owen Lattimore, a professor accused of un-American activities, they fell foul of McCarthy and were more or less exiled, first to Australian National University in Canberra in 1955-56 on a Guggenheim fellowship, and then to Baghdad University in 1957-59. Thereafter they came to London in 1960 where she spent most of the next two decades.
At first she divided her time between the London School of Economics and the School of Oriental and African Studies, until in 1964 she accepted an appointment at SOAS as Professor of Economics with special reference to Asia, which she held until 1978 with interruptions to go to Dar es Salaam in 1971-72 and Toronto in 1973. In due course she formed other attachments to British universities: to what became Templeton College, Oxford, from 1982 to 1985 and to Bradford University from 1989 to 1992. Somehow she managed to squeeze in seven years at INSEAD (Institut Europeen d'Administration des Affaires) in Fontainebleau between 1977-84, serving as Associate Dean in her last two years. By that time she was moving over more and more into management education.
These academic apppointments were combined with many other activities. She was a member of the Sainsbury Committee on the pharmacutical industry from 1965 to 1967 and the Medicines Commission in 1975-78, and joined a committee on Chemical Research Ethics set up by the Royal College of General Practitioners. She also served on a variety of associations of economists, chairing the Economic Committee of the SSRC/ESRC from 1970 to 1976, as Governor of the National Institute from 1974, on the Council of the Royal Economic Society from 1975 to 1980, a Director of the Commonwealth Development Corporation from 1975 to 1978 and a member of the Overseas Development Institute from 1992 to 1994. She received many honours, including honorary doctorates from the Universities of Upsala and Helsinki and an award in 1986 from the British Association of Energy Economists for her many distinguished contributions.
A few years ago, she joined forces with me in trying to persuade the European Court of Justice to refrain from using anti-dumping legislation against imports of low-cost Japanese photocopying machines, but without effect. The legislation was particularly unfair since the Japanese had helped to establish the industry in Europe. But the judges were unmoved by her arguments, leaving us convinced that they had very odd ideas of what constituted dumping.
Edith Penrose was petite, good-looking and very feminine. She had a balanced and attractive personality and spoke clearly and authoritatively. She was a popular member of Robert Mabro's Oxford Energy Policy Group from its foundation 20 years ago, the only woman present among the tycoons from the oil industry. What she had to say was always listened to with great attention and deservedly so. She was always well- informed, sensible and penetrating in her judgements and kind in her expression of them.
Edith Tilton, economist: born Los Angeles 29 November 1914; Associate Professor of Economics, University of Baghdad 1957-59; Reader in Economics, LSE and SOAS, London University 1960-64; Professor of Economics, SOAS 1964-78 (Emeritus), Head, Department of Economics 1964-79; Professor, INCEAD 1977-84 (Emeritus), Associate Dean for Research and Development 1982-84; married 1934 David Denhardt (died 1938; one son), 1944 Ernest Penrose (died 1984; two sons and one son deceased); died Waterbeach, Cambridgeshire 11 October 1996.