More than 200 Yale workers waving bright red picket signs marched to Woodbridge Hall Wednesday night, calling for greater job security amid ongoing labor negotiations with the University that began in March.

As they gathered outside Woodbridge under darkening skies, members of Local 34 — Yale’s union of clerical and technical workers — and Local 35, the University’s blue-collar union, once again demanded job security, carrying signs that said “Yale: Protect Our Jobs.”

Yale has a long history of clashes with Locals 34 and 35, whose current bargaining agreements expire at the end of the calendar year. And in recent months, the prospect of job cuts at the Yale Medical School, where around 100 workers have already been laid off, has exacerbated tensions with the unions.

“We’re the ones who do the work here,” said Local 35 President Bob Proto, to cheers from the crowd. “Yale didn’t just wake up one day, and say, ‘You deserve this.’ There’s a whole history here of dysfunctional relationships and struggle.”

Tuesday night’s demonstration is the latest chapter in a series of ongoing disputes between the University and its two officially recognized unions. Yale is currently contesting the legitimacy of a third potential union of Yale graduate students, Local 33, which filed union elections in 10 graduate departments with the National Labor Relations Board earlier this fall.

In May, a crowd of more than 1,000 members of the two locals marched on the Medical School demanding greater job security. At the time, union leaders argued that the layoffs were Yale’s attempt to hire inexpensive, non-unionized employees by moving Medical School jobs to Yale-New Haven Hospital. In response to these protests, University representatives responded to these protests that YNHH hiring had no influence on the Medical School layoffs and attributed the job cuts to budget constraints.

Tuesday’s demonstration was the second major labor protest on campus this fall. On Aug. 26, a group of 400 union members gathered in front of Old Campus to call on the University to include “job-security language” in the labor contract currently being negotiated.

Yale’s union contracts are negotiated every four years.

Demonstrators interviewed Tuesday night cited the cuts at the Medical School as one of several major problems with how Yale interacts with organized labor.

“I’m supporting our brothers and sisters, hoping for job security,” said Local 34 member Donovan Gianfredi, a medical assistant for Yale’s digestive diseases team. “We’re out of work, and the University doesn’t care. They don’t want to replace jobs.”

Gianfredi added that if the unions do not reach an agreement with the University, he would join other members of Locals 34 and 35 in a University-wide strike.

“It has been discussed, if that’s what we need to do to get our message across,” Gianfredi said.

In a statement to the News, Vice President for Communications Eileen O’Connor said Yale continues to hold new contract discussions with its unions and is “optimistic that new labor agreement terms can and will be peacefully achieved.”

The last time Locals 34 and 35 went on strike was in 2003, when failed negotiations kept the dining halls and other University facilities closed for three weeks. The 2003 strike was the seventh work stoppage at Yale in 34 years.

Ken Suzuki, the secretary-treasurer of Local 34, stressed that the union leadership will do all it can in the next few months to avoid that outcome.

In an interview outside Woodbridge on Tuesday, Suzuki said union members are focused on securing a peaceful resolution to the current negotiations. Still, during negotiations for the two previous contracts, he added, both unions reached agreements with Yale six months before the deadlines.

“This is going down to the wire, and we are working to settle on good contracts,” Suzuki said.