"Looking at that picture in terms of advocacy it's more about remembering there are people out there who are vulnerable and who do have difficult challenges in life and we shouldn't shove them all in the too hard basket," Grant said on Friday at the announcement of the winners at the National Portrait Gallery.

Her portrait is of a young man in his 20s, Charlie, who lives in the village with his father. He is one of the youngest residents of the village.

"We actually have a civic responsibility, particularly in this city, to care for our most vulnerable people," says Grant, who until moving to the NSW south coast six months ago, was a Canberra-based artist.

The NPPP judges found Grant's portrait compelling due to its "strong sense of humanness", says Chris Chapman, who, along with Robert Cook and Petrina Hicks, had the unenviable task of whittling down more than 3200 entries, the most the NPPP has ever received, to the final 43 now on display in Canberra until June 17, 2018.

The highly commended award went to Victorian photographer Filomena Rizzo for her portrait My Olivia.

From a young age, Olivia has experienced strong feelings and urges, tapping things a certain number of times, a consequence of genetic, biological and environmental factors. Now 11, with patience and the maturing of chemicals in her brain, she has outgrown the impulses, her mother says.

"The portrait has come from a very personal space and time," Rizzo says.

"When you put so much into an image and share it, it is wonderful that others see it. I am truly humbled and grateful to have won highly commended.'

Chapman said both the winner and the highly commended images conveyed an openness which drew the judges in.

"They're both images of young people, young people making their way in the world, young people dealing with their own particular struggles and I think they tell stories which are very poignant and very relatable," he said.

"The photographers have been able to allude to those bigger aspects of both of the subject's lives through images which have a real directness about them."

Grant was critical of the proposed development of the neighbourhood which threatens Ainslie Village. There is a big new housing development planned in the area and the ACT Government is looking at options for managing the village which can house up to 172 people with drug and alcohol, mental health and other complex problems.

"I find the development that goes on in this city obscene sometimes," Grant says.

"What about people? I believe in humanity and I just think it's really sad that our politicians have forgotten who their constituents are."

The portrait was part of a project held at the Ainslie Village, Self-ID, a collaboration between the residents and Canberra-based artists Tilly Davey, Blaide Lallemand and Grant.

Residents had their portrait taken if they chose to and then worked with collage and mixed media to create self portraits.

"When it came to Charlie I was very curious about his back story," says Grant. "I think it was his youth, and I have a son called Charlie, I was wondering, as a mother, how did he get to be there. I felt quite worried about him, tender towards him in a way.

"He was one of many we photographed that day in a makeshift studio off the kitchen. We did a whole heap of portraits that day and one of them happened to be Charlie. I knew when I shot it that it was just going to work."

The NPG awarded the art handlers' award earlier in the week to Stephanie Simcox for her portrait titled Joey.

People's Choice voting opens from March 23, 2018; the public can vote for their favourite image online at nppp.portrait.gov.au or in person outside the exhibition space.

The National Photographic Portrait Prize opens on March 24 and is on display until June 17, 2018. The exhibition will then tour around Australia.