Brendan Sexton, who as New York City’s sanitation commissioner initiated what at the time was the nation’s most ambitious mandatory garbage recycling program and hired the first women as uniformed workers in the department’s 105-year history, died on Tuesday at his home in Manhattan. He was 78.

The cause was prostate cancer, his daughter Dr. Tara Shelby Sexton said.

An indefatigable public servant, Mr. Sexton worked under five mayors. After leaving city government, he remained active as a civic leader: He oversaw the Municipal Art Society’s mandate for historic preservation, the Times Square Alliance and its millennial celebration in 2000, and the South Street Seaport Museum as it struggled to advance from municipal stewardship.

But it was his campaign for curbside recycling that had the greatest impact on New Yorkers. The City Council passed legislation in 1989 requiring millions of households to bundle newspapers, magazines and cardboard and separate them from other trash, and to place glass bottles and metal cans in their own plastic bags or receptacles for curbside pickup. The new rules were to be phased in over the next several years.

“What we are doing is working a cultural revolution, a social revolution,” Mr. Sexton, who had been sanitation commissioner since 1986, said at the time. “We are changing the way property owners manage their property, the way householders manage their kitchens.”

His goal was to have 25 percent of the city’s garbage recycled within five years. But with the city facing a budget gap by the early 1990s, the program proved prohibitively expensive. Today, according to the Sanitation Department, only about 17 percent of all the city’s garbage is recycled.

During Mr. Sexton’s tenure, which ended later in 1989, landlords were ordered to phase out incinerators in apartment houses. The city also embarked on a pilot resource-recovery program that burned garbage, generating steam to be sold to the power utility Consolidated Edison, and began an experiment to capture methane gas from landfills.

The challenges of disposing of millions of tons of solid waste annually captured national attention in the summer of 1987, when Mr. Sexton oversaw the ill-fated launch of what was probably the most famous garbage barge in history, the Mobro 4000.

With its landfill sites full, the city sought other places to bury solid waste. The Mobro, filled with 3,000 tons of garbage, departed from Long Island. But after the material was rejected by six states and three countries out of fears that it was contaminated with medical waste, the barge lumbered back to New York, ending its 162-day, 6,000-mile odyssey at a Sanitation Department incinerator in the Gravesend Bay section of Brooklyn.

Although Mr. Sexton would later play the role of aesthetic guardian with the Municipal Art Society, it was he who pursued a program under which vehicles that ignored alternate-side parking regulations were plastered with lurid chartreuse stickers proclaiming that they were illegally obstructing mechanical street sweepers. The City Council ended the sticker program in 2012.

“Brendan was a first-rate analytic talent who also possessed strong administrative skills and savvy,” said Norman Steisel, who preceded Mr. Sexton as sanitation commissioner during the Edward I. Koch administration and later served as David N. Dinkins’s first deputy mayor.

“He demonstrated an ability to navigate complex issues and collaborate with diverse political stakeholders, skills that enabled progress on things like launching the city’s landmark recycling system and cleaning up Times Square,” Mr. Steisel added, in an email.

Eric A. Goldstein, a senior attorney and New York City environmental director for the Natural Resources Defense Council, said by email that Mr. Sexton was “a great friend of our environment, and one of the nicest people to anyone and everyone who met him.” He added, “Even when he was delivering bad news, he did it in a way that made you want to like him.”

In 1986, two women who had completed their training were sworn in as the city’s first uniformed sanitation workers. The more than 130 men who took the oath with them cheered.

Brendan John Sexton was born on June 29, 1945, in Detroit. His father, also named Brendan, was a union leader and a sociology professor at New York University. His mother, Hilda Zack Rogin, was a professor at American University in Washington and also taught high school in Washington and New York. The family moved to New York when he was 4.

After graduating from Forest Hills High School in Queens, Mr. Sexton earned a bachelor’s degree in experimental psychology at New York University in 1969. (He would return to the university years later as a clinical professor at the Wagner Graduate School of Public Service.)

In addition to his daughter Tara, Mr. Sexton is survived by his wife, Karen Dalzell;. two sons, the actor Brendan Sexton III and David Zalk; three daughters, Amber Sexton, Oona Dalzell-Sexton and Zoë Dalzell-Sexton; four stepchildren, Eben Sexton and Lisa, Ilona and Carinna Abitbol; one grandchild; three step-grandchildren; and a sister, Patricia Hersh. His marriages to Lynn Ossa and Judith Ann Ford ended in divorce.

In the 1960s, Mr. Sexton was arrested for participating in civil rights demonstrations as a member of the Congress of Racial Equality; he was also a conscientious objector during the Vietnam War. In 1966, while he was still an undergraduate, he and Ms. Ossa, his wife at the time, and a friend, Jan Stacy, founded Encounter Inc., a treatment program for young drug abusers that operated in Greenwich Village until 1972.

Mr. Sexton was laid off by the Addiction Services Agency during the city’s fiscal crisis of the mid-1970s but was subsequently appointed to help resolve the crisis as a member of the Mayor’s Management Advisory Board.

“Suddenly the whole city opened up to me,” Mr. Sexton recalled. “After that, I wouldn’t work anywhere else.”

He became director of corruption prevention and management review for the city’s Department of Investigation in 1978. Two years later, he was named deputy director of the Office of Operations, and in 1983 he was appointed the office’s director, reporting directly to Deputy Mayor Nathan Leventhal.

When Mr. Leventhal was the city’s housing commissioner, he later recalled, Mr. Sexton, who was then at the investigation department, would periodically take him to task for one thing or another.

“I found his presence kind of troublesome,” Mr. Leventhal told The New York Times in 1986. “But when I became deputy mayor, he was the first person I called to come over and work for me. I let him loose on the entire city government, and no one was ever safe after that.”