Prisoners from Waikato's Waikeria Prison are renovating a Waikato Women's Refuge Te Whakaruruhau donated house.
The house will provide shelter for women and children who are victims of domestic violence.
Te Whare o Te Ao Marama, formerly the Maori Focus Unit in the Waikato prison, have spent six weeks working on the house, building fences, laying concrete and working on footpaths.
Up to six men at a time have been working off prison grounds for what they call Te Rau Aroha (a challenge of love).
The project is one of six run by Te Whakaruruhau.
Prison director Kevin Smith said the prisoners involved are passionate about their work.
"There is a sense of satisfaction when the men see what has been accomplished for others. They see that they have done something that will help keep someone else safe.
It can be motivating for them, giving them the drive to learn more about what they can do to break the cycle of violence."
Te Whakaruruhau chief Roni Albert said she has worked with men from the prison for nine years and sees their hard work and dedication as playing a vital role in helping them turn their lives around.
"Lots of the guys we see have come from violence themselves. They grew up in it and sometimes it's the reason they are where they are. Part of them making those positive changes is to give back. By supporting women and children who have suffered at the hands of violent men, they can see the impact of their choices and the value of making better decisions in the future."
The Department of Corrections manages more than 35,000 prison sentences and orders in the community each week.