Clyde W. Summers, 91, formerly of Fairmount, a law professor for 63 years and a leading labor-law scholar, died of complications of a stroke Saturday, Oct. 30, at Stapely, a retirement residence in Germantown.

Professor Summers taught at the University of Pennsylvania Law School from 1975 until suffering a stroke in 2005. From 1956 to 1975, he was a professor at Yale University Law School and previously was on the faculty of the law schools at the University of Minnesota and University of Toledo.

In September, Employment Rights and Employment Policy Journal published a special edition in honor of Professor Summers with several essays examining his contribution to labor and employment scholarship.

"His work on the unjustness and reform of the rule that employees working under contracts of indefinite employment are terminable at will unleashed a torrent of developments - scholarly, judicial, and legislative - focused on the rights of employees," editors Martin H. Malin and Douglas D. Scherer wrote in the edition's introduction. In the conclusion, they praised Professor Summers for his "service to the cause of union democracy and industrial democracy."

Professor Summers lectured all over the world and was the author of more than 100 articles in law journals and five labor-law and employment-law casebooks. He was an expert witness in labor-law litigation and was a consultant to state legislatures, including Pennsylvania's, and to the U.S. Department of Labor and other government agencies. He served on the New York Governor's Commission on Improper Union and Management Practices and the Connecticut State Labor Relations Board. He was past president of the International Society for Labor and Social Security Law.

"Those of us privileged to work with Clyde knew him as a patient listener who encouraged younger colleagues and was always ready to listen to a competing thesis," a friend, Alvin Goldman, wrote in a tribute. Goldman is professor emeritus at the University of Kentucky School of Law.

Michael A. Fitts, dean of the University of Pennsylvania School of Law, wrote in a tribute to Professor Summers, "He used to say that the life of the lawyer should be something more than cases and precedent - it should be about what is good, what is just, what is kind. He couldn't have described his own career better."

Professor Summers was an advocate for changes in labor laws to permit employees to be discharged only for just cause. "Employment at will," the common-law doctrine that employees could be fired for good reason, bad reason, or no reason, had been "set in concrete" in the United States for more than a century, he told The Inquirer in 1986.

Beginning in the mid-1970s, he said, U.S. courts began to rule in favor of employees in certain instances, including workers who were fired after refusing to lie under oath during an investigation of a company or who were let go after filing a workers' compensation claim.

These firings were improper, Professor Summers argued, because they were contrary to "public policy," meaning that the general good is best served if employees are not required to break a law to keep their jobs or if they are unafraid to exercise their right to file a claim.

Professor Summers was born in a tar-paper shack in Montana and grew up in several states in the Midwest where his father farmed during the Depression.

After earning a bachelor's degree and a law degree from the University of Illinois, Professor Summers earned a master of law degree and a doctorate in judicial science from Columbia University.

He was the recipient of Guggenheim, Ford, Marshall, Fulbright, and National Endowment of Humanities Fellowships and studied in Belgium, Sweden, Germany, and England.

He and his wife, Evelyn Summers, met on a blind date at a Valentine's dance in Ohio when he was teaching at the University of Toledo. They married in 1947.

Growing up on a farm, he learned to fix anything, she said, and enjoyed renovating their vacation home in Vermont and building stone walls.

In addition to his wife, Professor Summers is survived by sons Mark and Craig, daughters Erica and Lisa, a sister Majel Drake, and eight grandchildren.

A memorial service is yet to be scheduled.

Donations may be made to the Peggy Browning Fund, which provides fellowships for law students dedicated to improving the lives of workers, at 1528 Walnut St., Suite 1904,  Philadelphia 19102 or to the Association for Union Democracy, 104 Montgomery St., Brooklyn, NY, 11225.