More than 1200 people have called a new sexual harm helpline - most of them teenagers.
Safe to Talk launched on June 1, after a test run in Canterbury from February 19.
It provides text, phone, and email support for survivors of sexual assault and harassment, and is staffed by experienced sexual trauma professionals.
Clinical lead Dr Siale Foliaki said they hoped the anonymity of the service would help people who otherwise would stay silent ask for help.
"I think the area of sexual harm is an incredibly sensitive and really difficult area. If a person has been exposed to that type of harm, often seeking help can be complicated.
"One of the things we were hoping for was that contact, without being face-to-face, could give increased access.
"Because there is privacy that allows people to make contact, and lead them to maybe later engage in face-to-face work, addressing the harm that occurred in their life."
As part of the Herald and Newstalk ZB's Speaking Secrets podcast series, a man publicly spoke for the first time about being sexually violated as a child attending a Catholic school.
He said the first time he spoke about it was when he called a sexual abuse helpline.
Foliaki said many sexual assault survivors felt ashamed, and also wanted to protect people they loved from knowing what had happened.
This could make it very difficult to speak about it without the shield of anonymity.
"For some people the mere fact of being able to share their experience leads to an increase in overall wellbeing, and then they're able to go out there and seek further help," he said.
"About 6 per cent of people have been exposed to more severe sexual harm.
"If you think about that, that's tens of thousands of New Zealanders. So our expectation is that, over time, we're going to get calls from all of those people.
"For those at the more severe end, there's overwhelming evidence that they will experience some sort of long-term mental health issue. Not all, but a significant majority.
"So understanding the issues around sexual harm also means that people can start discussing other issues that have occurred in their lives, and they can get help for all of those things."
Of the people who have called the helpline in its first month, the most commonly reported issue was historic sexual abuse.
Women were 83 per cent of callers, and men 17 per cent.
The most common age group was 13-19-year-olds, followed by 40-44-year-olds.
About 5 per cent of those who got in contact were referred to a face-to-face counsellor.
Some people called the helpline because of concerns for another person, and used the service to get information on how to support friends or family through sexual harm.
Safe to talk is available for free 24/7.
Call 0800 044 334
Resources and webchat at www.safetotalk.nz