Greenpeace is celebrating what it calls a "win for democracy".

The High Court has today ruled the organisation is entitled to register as a charity.

It ends a more than eight-year long legal battle which began when the Charities Registration Board rejected Greenpeace's application.

Executive Director Russel Norman told Heather Du Plessis Allan a vibrant democracy needs strong non-government organisations.

"One of the threats to NGOs is charitable status. I don't want to live in a society where governments can threaten the charitable status of organisations that cause them too much trouble."

He says it's a matter of principle.

"It threatens NGOs, particularly the smaller ones. If they lose their charitable status, a lot of donors won't necessarily give to them because they will think 'why haven't you got charitable status, what's wrong with you?'"

Charities law specialist Sue Barker says it's a long time coming.

"It's a fantastic result for all charities that advocate for their charitable purposes."

She says getting registered charitable status is a gateway to an increasing number of tax privileges.

However, Barker argues it's about more than tax.

"It's about the framework for charity law in New Zealand and it's about supporting charities doing work for the benefit of all of us."