Activists around the world rallied for May Day, a symbol of workers' rights observed on May 1.
At Foley Square, protesters with the group United Here! marched in support of immigrant and laborers' rights.
"We need to fight to let them know that without us, there is no United States," one member of a local food workers' union said.
More than three dozen unions joined the rally, and among the participants was Gerard Cerda, a vendor at Madison Square Garden who says he wants to see working conditions for immigrants to improve.
Daniel Mateo, a fast food worker at John F. Kennedy International Airport, says he feels that he is being taken advantage of in the workplace.
"I want my rights," he says. "I want a future."
Around the country, about 30,000 people were expected to march in similar rallies.