Warren Bennis, who was regarded as a foremost expert in the principles of effective leadership, died July 31 at 89. (Photo by Philip Channing/USC)

Warren Bennis, a professor, scholar and author who was recognized for decades as one of the world’s foremost experts in the principles and practice of effective leadership, died July 31 at a hospital in Santa Monica, Calif. He was 89.

He had complications from pneumonia, said his daughter, Kate Bennis.

A member of the generation that grew up during the Great Depression and fought in World War II, Dr. Bennis was a man of many experiences and achievements, which included the authorship of almost 30 books, many of them regarded as bibles for those who produced the best results from institutions large and small.

He held a PhD from the Massachusetts Institute of Technology, consulted at the highest levels, had been a college provost and president, and was much in demand as a speaker, writer and thinker in the areas of leadership and organizations.

In a sense, his multifaceted life reflected the beliefs he developed about the nature and practice of leadership. Among those qualities he found important were the humanistic virtues, including creativity, vision and openness to ideas and experience, as well as genuine concern for the lives of those who are led.

Warren Bennis, who was regarded as a foremost expert in the principles of effective leadership, died July 31 at 89. (Photo by Philip Channing/USC)

Few thinkers, writers or scholars possessed greater rhetorical gifts for formulating memorable mottoes, aphorisms and observations about how to achieve and inspire success.

In distinguishing between the unimaginative manager and the far-seeing leader, Dr. Bennis said that the former “does things right,” while the latter “does the right thing.”

He would also say that while “the manager has his eye on the bottom line,” the true leader “has his eye on the horizon.”

Although leaders are often regarded as necessarily above and apart from those they lead, Dr. Bennis emphasized the importance of joint effort.

“None of us,” he said, “is as smart as all of us.”

Those who aspired to lead others and develop their talents, he maintained, needed to learn to understand themselves and develop their own best selves. In holding to such principles, he showed an affinity for the ideas of humanistic philosophy and a belief in the richness of human potential that often goes untapped.

For him, leadership was both an ad­ven­ture and an art, which sprang not from textbook recipes but from such practices and qualities as intuition, observation and an effort to meld classroom theory with immersion in the real world. It was his belief that not only success but also failure taught invaluable lessons.

Warren Bennis was born in New York City on March 8, 1925. A failure at several businesses, his father moved the family from New Jersey to Los Angeles, where Dr. Bennis graduated from high school. He also worked in his father’s hard-pressed malt shop, favoring classmates with extra scoops of ice cream.

Then World War II broke out and after a short stint as a riveter in an airplane factory, Dr. Bennis enlisted in the Army. By December 1944 he was in Europe, a teenage second lieutenant in an infantry division. He may have been, he wrote in a memoir, the youngest officer in the European Theater.

After the war, in which he was awarded the Bronze Star Medal and the Purple Heart, he graduated from Antioch College in Yellow Springs, Ohio, in 1951 and obtained his MIT doctorate in 1955, concentrating on social science and economics. He went on to head the organizational studies department there.

By 1967, he had combined his interests in academic study and organizational management by taking the post of provost at the State University of New York at Buffalo. Four years later, he assumed the presidency of the University of Cincinnati.

While in that post, he wrote two books on the academic world and leadership: “The Leaning Ivory Tower” (1973) and “The Unconscious Conspiracy: Why Leaders Can’t Lead” (1976).

His presidency, he said, was marked by years of hard work. Then came what he described as a “coronary event.” It has also been characterized as a heart attack, which led him to move back to the West Coast. Returning to his earlier career of teaching, writing and consulting, he joined the faculty of the University of Southern California.

Describing him as visionary and transformational, USC President C.L. Max Nikias called him one of a rare group of pioneers who could both anticipate the needs of a world of change and guide that change by his work.

Of his more than two dozen books, most were written at USC, where he headed a leadership institute. His books included “Leaders” (1997) and “On Becoming a Leader” (1989), as well as “An Invented Life” (1993), “Organizing Genius” (1997) and “Managing the Dream” (2000).

His first marriage, to Clurie Williams Bennis, ended in divorce. Survivors include his wife of more than two decades, Grace Gabe of Santa Monica; three children from his first marriage, Kate Bennis of Charlottesville, Va., John Bennis of Costa Mesa, Calif., and Will Bennis of Prague; two stepdaughters, Nina Freedman of Santa Monica and Eden Steinberg of Cambridge, Mass.; and 10 grandchildren.

Writing, he told a USC interviewer in 2010, “is a way of feeling I’ve influenced the lives of others for the common good. Running through all my work, I think there’s a humanitarian impulse that if we work together for a good cause, we can change the world.”