Auckland's first regionwide count of homeless people will kick off tomorrow with the help of up to 1000 volunteers.
The ambitious project aims to paint a clearer picture of rough sleeping by collecting census-like data about the city's homeless population.
Auckland Council is funding the $375,000 cost of the count, which starts at 9.30pm and runs until just after midnight.
Volunteers in groups of three will work across the Auckland region, from Wellsford in the north to Waiuku in the south, and from Piha in the west to the Hūnua Ranges in the east.
Housing First Auckland project manager Fiona Hamilton said she had been "blown away" by the number of volunteers who have registered to help.
Aucklanders had become increasingly concerned by the homeless problem in recent years as evidenced by how many had contacted support groups offering to lend a hand.
Helping the count "is a tangible thing they can do because gathering the data about homelessness is a really important step to addressing it", she said.
Currently, government agencies and support groups can only estimate how many people are homeless.
Previous head counts by non-government groups were much smaller in scale and mostly focused on the CBD, where it is believed between 300 and 500 people are sleeping rough.
A 2015 University of Otago study estimated there were around 4200 rough sleepers across the country, and about 771 in Auckland.
It is hoped Monday's count will not just provide a tally of the homeless population but also new insights.
Volunteers will ask those they meet whether they want to take part in a survey, while the results of the count will be combined with data about how many people are living in Government-provided emergency accommodation, such as motels and refuges.
It could help uncover people and families who had not yet sought help from the Government or community organisations, said Moira Lawler, chief executive of Methodist Church support group Lifewise.
"There will be an element of people, who either don't know where to go or are embarrassed or ashamed at their circumstances because nobody expects to end up homeless," she said.
Equally as important as undertaking the count was ensuring its data was used meaningfully, Hamilton said.
"We need to ensure it is not just gathering data for the sake of it, but that it feeds into an active plan that informs co-ordinated action," she said.
"Ideally this would include [the development of] a national strategy to address homelessness."