Two Green Party MPs are joining the growing exodus from Parliament.
Catherine Delahunty and Steffan Browning have both announced they won't be seeking re-election next year.
Former Labour leader and Mt Albert MP David Shearer is also leaving to take up a role at the United Nations in South Sudan.
All but Mr Shearer won't formally leave Parliament until nearer the election - likely to be near the end of 2017.
"I'm very proud of my eight years as a Green Party MP, and the many, many years I spent before that as an activist fighting for women, our environment, and the rights of tangata whenua," Ms Delahunty says.
She holds the water, education and te Tiriti o Waitangi portfolios for the party.
"I feel particularly proud of the work I've done around building a quality, more inclusive public education system, leading our party's nationwide campaign for swimmable rivers, speaking up for the people of West Papua, and working for a national register of contaminated toxic sites."
She says her life away from politics will be spent writing and being with family, however intends to continue her activism and community building.
Mr Browning says in his five years at Parliament, he's been able to work with "some of the most innovative New Zealanders "who are creating a more sustainable future for our country, today".
He says a highlight of his time was his spray-free streets and parks campaign and having his Consumers Right to Know Member's Bill drawn which, if passed will let the public know where their food is from and where it is produced.
Mr Browning says he'll continue to push the issues he cares about after leaving Parliament.