Jane F. McAlevey, a fierce labor organizer and scholar who trained tens of thousands of workers across the globe in strategies for taking charge of their unions and shaping them, died on Sunday at her cabin in Muir Beach, Calif. She was 59.

Her stepbrother Mitchell Rotbert said the cause was multiple myeloma. Her primary home was in Manhattan.

Ms. McAlevey (pronounced MACK-a-leevee) dedicated her life to increasing working-class power. She believed that worker-driven unions — led from the bottom up rather from the top down — were the most effective engines to combat economic inequality.

In her writings, including for The Nation, as what the magazine described as its “strikes correspondent,” and in frequent media interviews and podcasts, Ms. McAlevey became a vocal critic of what she saw as the complacency, ineptitude and corporate collusion of many U.S. labor leaders.

“What almost no union does is actually organize their members as members in their own communities to build community power,” she said in an interview for this obituary last November. “I teach workers to take over their unions and change them.”

After leading successful campaigns for the A.F.L.-C.I.O. and the Service Employees International Union from 1997 to 2008, Ms. McAlevey transitioned to consulting, coaching labor groups across the country on how to energize the rank and file, attract new members and fight off employers’ aggressive anti-union tactics.

She also worked with immigrant rights organizations, tenant groups and climate activists and traveled internationally, advising German hospital unions, Irish communications workers and labor organizers in Canada, Australia and the United Kingdom.

A magnetic speaker with a dry sense of humor, Ms. McAlevey expanded her global reach in 2019. She led a free, intensive six-week online course, “Organizing for Power,” at the Berlin-based Rosa Luxemburg Foundation, a democratic socialist nonprofit. Over four years, 36,000 people in 130 countries logged onto the workshops, which were simultaneously translated into a dozen languages, including Arabic, Hindi, Portuguese and Russian.

She also drew about 4,500 participants over four years to workshops at the U.C. Berkeley Labor Center, where she was a senior policy fellow. In 2022, United Food and Commercial Workers local No. 770, a large Southern California union, sent 100 members and staffers to the workshops as it prepared to bargain with grocery chains, the group’s president, Kathy Finn, said.

As a result, the union opened staff-led negotiations to rank and file workers. The transparency led to “huge numbers of members voting to strike,” Ms. Finn said, a turnout that elicited corporate concessions, averting a walkout at the last minute. “More and more unions are using her tactics,” she said.

Ms. McAlevey’s books and courses drew on long-established organizing techniques, said Kate Bronfenbrenner, director of labor education research at Cornell University. But, she added, “Jane’s charisma and her teaching methods inspired people around the world, especially young people, to use their rank and file power to organize.”

Jane Frances McAlevey, the youngest of seven siblings, was born in Manhattan on Oct. 12, 1964. Her mother, Hazel (Hansen) McAlevey, died of breast cancer when Jane was 5. Her father, John F. McAlevey, was a local politician in Rockland County, N.Y.

Growing up in suburban Sloatsburg, N.Y., where her father was mayor, Ms. McAlevey accompanied him to campaign events, civil rights marches and protests against the Vietnam War.

“I got the fighter pilot gene from my old man,” Ms. McAlevey said of her father, who flew bombers over Germany during World War II.

As a student at the State University of New York at Buffalo, Ms. McAlevey was drawn into protests against tuition hikes and was elected student body president. She went on to lead the state university system’s 64-campus student association.

In April 1985, when the board of trustees was resisting divesting from companies doing business in South Africa, Ms. McAlevey hid a chain and padlocks under her dress and helped hundreds of students occupy a SUNY building. She served 10 days in jail for trespassing.

After college, she spent a year in Central America teaching people to read and rebuilding homes in a war zone in Nicaragua. Back in the United States, she worked for several nonprofits, including the Highlander Research and Education Center in Tennessee, helping poor communities fight chemical plant pollution.

After a decade in the environmental justice movement, Ms. McAlevey joined the A.F.L.-C.I.O. to lead an innovative multi-union campaign organizing nursing home workers, taxi drivers, janitors and city clerks in Stamford, Conn., a corporate hub with few union members at the time.

Workers were upset not just about wages and benefits, but also about the lack of affordable housing in the Stamford area, Ms. McAlevey found. She broadened the union campaign to push for housing, an approach she called “whole worker organizing.”

Labor organizing, Ms. McAlevey said, “is more than what happens when you punch the clock.”

“It’s bigger than that,” she said. “Do your kids have a good school to attend? A clean and safe park? Affordable housing? Transportation?”

Over four years, the Stamford Organizing Project unionized and won contracts for more than 4,000 workers while partnering with community groups to save public housing from demolition.

After joining the Service Employees International Union in 2002, Ms. McAlevey campaigned to organize nurses and other hospital staff in Nevada, a so-called right-to-work state, in which employees cannot be required to join unions. This also meant that union-represented workers could forgo paying dues, weakening labor’s clout. Ms. McAlevey was credited with reviving a moribund local chapter and leading strikes to gain contracts with higher wages and better benefits.

But her four-year Nevada tenure was tumultuous. She was nicknamed “Hurricane Jane,” and some local union officials resisted her initiatives. Her biggest fight was with the S.E.I.U.’s national leadership, which at the time was forging private deals with hospital chains to restrict strikes in some areas, including Nevada, in exchange for tolerating organizing elsewhere.

Ms. McAlevey left the S.E.I.U. in 2008. The next year, she tested positive for the BRCA1 breast cancer gene and underwent preventive surgeries to remove her ovaries, uterus and breasts. While recovering, she wrote a memoir, “Raising Expectations (and Raising Hell): My Decade Fighting for the Labor Movement” (2012), with the journalist Bob Ostertag. It laid bare with unusual candor not just the tactics of worker combat with hospital chains in Nevada, but also the internal union power struggles that sabotaged its gains.

Her account led to a new career. Invited to study for a Ph.D. at City University of New York, she turned her dissertation into a new book, “No Shortcuts: Organizing for Power in the New Gilded Age” (2016). It dissected a dozen campaigns — both successes and failures — to offer a nuts-and-bolts guide for organizers.

Labor and progressive groups waste energy on “feel good” mobilizing and “eventism,” such as rallies of supporters and news conferences, Ms. McAlevey contended. She advocated “deep organizing” — patient, one-on-one conversations to persuade indifferent or hostile workers.

Building large, strike-ready majorities within companies could counter the rightward drift of blue-collar voters, she believed.

Ms. McAlevey loved horses and owned one named Jalapeño, carting him from one city to the next and joking that he was her “significant other.”

In September 2021, Ms. McAlevey was diagnosed with multiple myeloma. She underwent chemotherapy and a bone-marrow transplant only to find out after collapsing on a picket line in Oakland that the treatment had failed.

Even after doctors told her that she had just weeks to live, she defied expectations, celebrating the publication of her fourth book, “Rules to Win By: Power and Participation in Union Negotiations” (2023), traveling to Ireland to research a fifth book, and lecturing online to workers from New Zealand to Zambia.

Ms. McAlevey is survived by four siblings: Benedict, John, Thomas and Birgitta McAlevey, as well as two stepbrothers, Mitchell and Clifford Rotbert. Her sister Catherine died of breast cancer in 2013, and her brother Peter died of liver cancer in 2014.

In April, with her cancer “attacking with a ferocity that has taken away the breath even of my medical team,” as she put it, Ms. McAlevey posted an open letter to family, friends, colleagues and newsletter subscribers — titling it “I Have Loved Being in This World With You” — reporting that she had entered hospice care at home.

Nonetheless, in May, she published a final article in The Nation dissecting the United Auto Workers’ election defeat at an Alabama Mercedes plant. Among other missteps, she wrote, the union had failed to rally the local community around its campaign.

She remained true to her cause till the end. Even as she spent her remaining time with loved ones, she wrote, she would be “loudly applauding every worker in every fight against what has become a rapacious, vicious new gilded age elite.”