New Zealand's Council of Trade Unions says Pacific Islanders brought in under the Recognised Seasonal Employer scheme need union representation.
The RSE scheme has been deemed generally successful in its first year but there have been problems - not least I-Kiribati workers who returned home in debt.
There have also been accusations of overcrowding while some I-Kiribati have broken the terms of their visas and are in hiding from New Zealand immigration officials.
The CTU president, Helen Kelly, says changes have to be made to the way the scheme runs.
"We're calling for them to be employed on standardised agreements in their own language. We want the pastoral care element of their employment to be separated out from their employer and carefully monitored. We want a funded representation for these workers so that they can actually have Pacific unionists going into these workplaces."
Helen Kelly says the New Zealand Government seems open to their ideas but it yet to make a commitment.