The Amalgamated Workers Union is calling for reforms to New Zealand's RSE workers scheme.
The union leads demands for fairer pay and better living conditions for migrant workers from the Pacific Islands who have limited worker rights in New Zealand.
Union regional organiser, Michelle Johnstone, said RSE workers had no negotiating power with their employers and most were paid on piece rates that had not increased over the last decade.
"They need to be able to have bargaining power with their employer, because they're bonded to their employer if they have a disagreement or feel they're not getting a fair choice, or even abused," she said.
"They can't leave. They can't leave their accomodation. They can't, like you and I can, get a job. If we don't like the place that we're living, we can go somewhere else. These guys cannot do that."
Johnstone said most RSE workers also paid heavy expenses on accomodation and health insurance.
"There's no average that they can't go below, so as long as they're making just above ... the minimum hourly rate which is $22.10, it's legal.
"It's not right for the amount of work, and hard work that these guys do," Johnstone said.