About 900 volunteers are out finding and surveying rough sleepers in Auckland's first homelessness census.

Photo: RNZ

The count runs from 9.30pm to 12.30am tonight across the entire region.

Small teams of volunteers, each with an experienced community worker at the helm, were approaching and surveying people who appeared to be sleeping rough.

There was no obligation for the homeless people to take part but those who did would be asked about 20 questions about their circumstances.

Previous homeless counts had focussed on the central city but this one would cover the entire region.

Housing First, the group overseeing the operation for the Auckland Council, had been working with community groups in the lead up to try to identify where rough sleepers were most likely to be.

Photo: RNZ

The count, known as a point-in-time survey, had limitations because homelessness was fluid and numbers could change from night to night.

But the Auckland Council and Housing First said it was the best way to get the most accurate picture possible.

They planned to use the information to understand how much help was needed and how to best target it.

Wilf Holt from Auckland City Mission briefed the volunteers at the central hub at Eden Park, warning them to approach potential rough sleepers sensitively, because of both respect and personal safety.

"You are going to be visiting people in their bedrooms. If somebody shines a torch in your face while you're sleeping...you're going to get aggrieved," he said.

The volunteers were encouraged to get information from those happy to take part - but not to put themselves in unsafe situations.

"If it looks dodgy, smells dodgy, sounds dodgy, it probably is dodgy so there is no harm in backing off, " he said.