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

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

A tireless public servant, Mr. Sexton served under five mayors. After leaving city government, he remained active as a civic leader: he oversaw the Municipal Art Society’s historic preservation mandate, the Times Square Alliance and its 2000 millennium celebration, and the South Street Seaport Museum as it struggled to get out of municipal stewardship.

But it was his campaign for curbside recycling that had the biggest impact on New Yorkers. The city council passed legislation in 1989 requiring millions of households to bundle and separate newspapers, magazines and cardboard from other waste, and to put glass bottles and metal cans in their own plastic bags or bins for collection. The new rules would be gradually introduced over the coming years.

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

His goal was to have 25 percent of the city’s waste recycled within five years. But when the city faced a budget deficit in the early 1990s, the program proved unaffordable. According to the Sanitation Service, only today about 17 percent of all waste in the city is recycled.

During Mr. Sexton’s term, which ended later in 1989, landlords were ordered to phase out incinerators in apartment buildings. The city also embarked on a pilot resource recovery program that burned waste and generated steam that was sold to the power company Consolidated Edison, and began an experiment to capture methane gas from landfills.

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

With landfills full, the city looked for other places to bury solid waste. The Mobro, filled with 3,000 tons of trash, left Long Island. But after the material was rejected by six states and three countries over fears it was contaminated with medical waste, the ship trudged back to New York and ended its 162-day, 6,000-mile odyssey to a Sanitation Department incinerator in the Gravesend Bay. part of Brooklyn.

Although Mr. Sexton would later play the role of aesthetic guardian at the Municipal Art Society, it was he who pursued a program in which vehicles that ignored alternate-side parking rules were plastered with lurid chartreuse stickers proclaiming that they were on illegal wise mechanical street sweepers. . The city council ended the sticker program in 2012.

“Brendan was an analytical talent of the first order who also had strong administrative skills and wisdom,” said Norman Steisel, who preceded Mr. Sexton as Sanitation Commissioner during the administration of Edward I. Koch and later served as the first deputy mayor of David N. Dinkins.

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

Eric A. Goldstein, a senior attorney and environmental director in New York City 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 who met him . .” He added, “Even when he delivered bad news, he did it in a way that made you want to like him.”

In 1986, two women who 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 labor leader and professor of sociology 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 four.

After graduating from Forest Hills High School in Queens, Mr. Sexton earned a bachelor’s degree in experimental psychology from 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 Dalzeell; two sons, 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; a small child; 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 still a student, he and Mrs. Ossa, his wife at the time, and a friend, Jan Stacy, founded Encounter Inc. on, a treatment program for young drug users that operated in Greenwich Village until 1972.

Mr. Sexton was fired by the Addiction Services Agency during the city’s budget crisis in 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 want to work anywhere else.”

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

When Mr. Leventhal was the city’s housing commissioner, he later recalled, Mr. Sexton, who then worked in the research department, would occasionally scrutinize him for one thing or another.

“I found his presence quite awkward,” Mr. Leventhal told The New York Times in 1986. “But when I became deputy mayor, he was the first person I called to come work for me. I unleashed him on the entire city council, and after that no one was safe anymore.”