Unions are looking at ways to increase membership.
A new MBIE report shows nearly 90 percent of those working in industry are not members of a union.
The study looked at 240,000 small and large businesses.
Council of Trade Unions president Richard Wagstaff told Mike Hosking union membership is now slowly growing.
"Of course we would like to be bigger and have more people be part of the unions, and that's constantly a priority for us."
He said New Zealand is following international trends.
"Countries such as the Scandinavians and the Europeans still have really high union density but countries like US and Australia are in the same place as us."