Charles (Cork) Walgreen III, the grandson of Walgreens founder Charles Walgreen Sr.

DEERFIELD, Ill. — Charles (Cork) Walgreen III, who led Walgreen Co. for nearly three decades, died last month at age 80.

Walgreen, whose grandfather, Charles Walgreen Sr., opened the first Walgreens drug store in Chicago in 1901, was born in 1935 to Mary Ann Leslie and Charles Walgreen Jr. He would go on to become the third Walgreen to lead the company.

Last year, in honor of his 80th birthday, he was a special guest at the Walgreen Alumni Association’s fall luncheon. Alex Gourlay, co-chief operating officer of Walgreens Boots Alliance Inc., was among the several hundred people in attendance.

“As I listened to the tributes and spoke with Mr. Walgreen,” Gourlay said, “I was struck again by how he led our company — with a great singular focus on his customers, with humility and a very clear sense that Walgreens needed to stand for value and care in the community. He made courageous decisions in that straightforward framework and built the Walgreens we know today as customers, employees and partners. I counted myself grateful whenever I was fortunate enough to spend time with him and his family.”

Walgreen is credited with leading the company through many big strategic changes. When he became president in 1969, the company was not meeting its profitability goals and growth targets. But under his leadership, Walgreens refocused on its core drug store business.

Walgreens by that time had a number of varied businesses, including Wag’s (its chain of freestanding restaurants); laboratories and manufacturing plants for private label products, and joint interests in such businesses as optical services; grocers and the Mexico-based Sanborn’s department store chain. Those businesses were sold off, beginning in 1976 and culminating in the sale of the Wag’s restaurants to Marriott Corp. in 1988.

He did more than establish what would be the company’s lasting focus on pharmacy services, customer convenience and investing back into the business. He also committed to focusing on core product categories of health care items, beauty and photo. As the chain expanded, he changed the company’s view of profitability, switching the focus from profit per store to profit per customer visit.

He was also a strong proponent of technology and innovation. In the early 1980s the company connected all its pharmacies via Intercom, a computerized prescription processing system, and under Walgreen’s leadership the drug store chain automated its distribution centers and embraced point-of-sale scanning at the checkout.

By the early 1990s, he led another transformation — to freestanding drug stores versus traditional locations in strip malls — on what became known in the company as “Main & Main, the best corners in America.” The stores featured drive-through pharmacies, which Walgreens also pioneered in the industry.

During his tenure as chief executive officer, which began in 1971 and ended in 1998, the company grew from 561 stores to more than 2,400; its sales grew from $817 million to $13 billion; its stock split six times; and it posted 23 consecutive years of record sales and earnings growth. Through it all Walgreen shunned personal publicity and gave his management team and employees credit for the company’s successes.

Walgreen got his start at the company in 1952, working as a stock boy after school and during vacations. He graduated from the University of Michigan in Ann Arbor with a bachelor’s degree in pharmacy in 1958, and returned to Walgreens the next year in his first professional capacity, serving as a pharmacist in the store at 7510 N. Western Ave. in Chicago, which is still open today. In 1963, he was named administrative assistant to the vice president of operations and was elected to the company’s board of directors.

He then held a series of positions of increasing responsibility, including being named district manager (1965), Western regional director (1966) and vice president (1968). He became company president in 1969, president and CEO in 1971 and chairman and CEO in 1976.

Walgreen served as CEO until his retirement in January 1998. He remained chairman until August 1999 and then was chairman emeritus until 2010.