Mr. Bolles at his home in Danville, Calif., in 2006. (Ben Margot/AP)

Richard N. Bolles, who prodded, coached and inspired millions of job seekers with his best-selling employment guide “What Color Is Your Parachute?” — a manual whose popularity, if not utility, was rivaled at one time on the bestseller charts only by “The Joy of Sex” — died March 31 at a hospital in San Ramon, Calif. He was 90.

The cause was a stroke, said a son, Gary Bolles.

Mr. Bolles entered adulthood as a physics student at Harvard University, was ordained as an Episcopal priest and became known to generations of Americans — after the publication in the 1970s of his now-classic volume — as a guru of job searches.

His winding career served as an example of what one could achieve through the principles he preached. Distilled to their essence, those principles included the importance of discovering one’s strengths, of identifying an employer’s needs and of uniting the two through creative determination.

When addressing the desperately out of work, Mr. Bolles knew whereof he spoke. In 1968, after serving as pastor of Grace Cathedral in San Francisco, he was let go in what he described as a “budget crunch.” His house had recently burned down, and he, his wife and their four children were living in a motel.

Mr. Bolles eventually found work with United Ministries in Higher Education, a job that took him to campuses where he met chaplains who also feared for their professional future.

With them in mind, he researched, wrote and self-published in 1970 “What Color Is Your Parachute? A Practical Manual for Job-Hunters and Career Changers.” The titular parachute, he said, was inspired by the expression, common at the time among people weary of their jobs, that they wanted to “bail out.”

“I always thought of an airplane,” Mr. Bolles told Workforce magazine, “so I playfully would respond, ‘What color is your parachute?’ ”

To Mr. Bolles’s surprise, the book drew readers far beyond the clergy. In 1972, the book was picked up by Ten Speed Press in Berkeley, Calif. It went on to sell more than 10 million copies over four decades. By the early 1980s, “Parachute” was competing with “The Joy of Sex” for the distinction of longest time spent on the New York Times trade paperback bestseller list.

As Mr. Bolles described it, his volume was “a book of hope masquerading as a job-hunting manual.” He traced its enduring relevance not only to the vagaries of job markets, but also of personal fortunes. At all times, Mr. Bolles noted matter-of-factly, people are retiring, falling ill or dying. Those changes open up jobs for those who are seeking new or more-satisfying employment.

The success of a job search, Mr. Bolles argued, was determined by the seeker’s ability to pinpoint their talents and then find the employer they would best serve. He put little hope in job postings and résumé blasts and instead encouraged job seekers to form personal connections through means such as the informational interview — a term he helped popularize.

“Your success at the job hunt is directly proportional to two things,” he told The Washington Post in 2009, “how persistent you are and how much time you devote to it.” He pushed readers to treat a job search like a full-time occupation. Among his pointers: It is always safer to overdress than underdress for an interview.

But his most meaningful guidance was philosophical in nature.

The most common mistake a job seeker can make, he told NPR in 2014, is “assuming the employer has all the power.”

“In reality, an interview should be viewed as a conversation,” he said. “It’s two people — the activity’s most analogous in other human behavior to dating. Do we like each other? Do we want to try going steady?”

Richard Nelson Bolles was born in Janesville, Wis., on March 19, 1927. His mother was a homemaker, and his father was an editor with the Associated Press. A brother, Don Bolles, was an investigative journalist for the Arizona Republic, covering organized crime and public corruption, when he died in a car bombing in 1976.

Mr. Bolles served in the Navy at the end of World War II, then graduated from Harvard in 1950. He was counting on a career in the sciences when he was inspired to join the ministry. He studied at the General Theological Seminary in New York and was ordained in 1953.

Mr. Bolles’s books included “The Three Boxes of Life and How to Get Out of Them: An Introduction to Life/Work Planning” (1978), “How to Find Your Mission in Life” (1991) and “The Job-Hunter’s Survival Guide: How to Find Hope and Rewarding Work, Even When ‘There Are No Jobs’ ” (2009).

His marriages to Janet Price, Geralyn Burton and Carol Christen ended in divorce, and he left the ministry in 2004.

Survivors include his wife of 13 years, the former Marci Mendoza, of Danville, Calif.; three children from his first marriage, Stephen Bolles of Eden Prairie, Minn., Sharon Bolles of Talent, Ore., and Gary Bolles of San Francisco; 10 grandchildren; and two great-grandchildren. A son from his first marriage, Mark Bolles, died in 2012.

Speaking to NPR, Mr. Bolles acknowledged that although he updated his book annually, its central wisdom had remained the same since the 1970s. People might conduct job searches differently — online, for example, rather than in the pages of the Sunday newspaper — but “the content of the interview has not changed one whit over the years.”

“It’s still two people circling each other, trying to figure out if they like each other enough to actually spend time together in a productive relationship,” he said. “I think that has remained the same because human nature has not changed.”