The last time Len Jenkins was found wandering the streets near his home in Portishead a concerned stranger made sure he was returned safely.
But Len's son, Keith, worries constantly about his 94-year-old father.
Len's dementia means he cannot always remember where he is. His carers have put signs on his front door telling him not to go out alone but still he occasionally forgets.
Keith, 76, lives 10 miles away and still works, so is not able to watch him constantly.
But he now has a new way to keep an eye on his father. Len was selected by Avon and Somerset Police to receive one of 30 new GPS tracker devices being handed out to people living with dementia.
They're being given to people most at risk of going missing. It means both families and the police can log in to an app and track where they are.
The devices can be worn like a lanyard or fastened onto clothing.
"I can relax a bit more," says Keith. "I can relax because I feel like everything is in place to help him as much as physically possible."
Keith adds: "I could put him in a home where he will be 100% safe… or I could bring him home where he wanted to be where he's probably not quite as safe.
"And so the systems we've put in place here, I think are the best compromise. He's at home, he's happy and in my conscience I've done everything to keep him safe."
The project was the idea of Sergeant Stuart King who saw there was a need to do something to help.
"Over the last 18 years of my police service it's been a regular occurrence and, in fact, I've seen it more in recent years where we're getting more and more calls to people who've got dementia who are being found by members of the public, either lost or in a distressed state," Sergeant King says.
"And there are certain incidents I've attended as well that have stuck with me. Some have ended up in tragic circumstances and others were people living with dementia who've travelled across cities to try and find childhood homes that are no longer there.
"So it was these sorts of incidents that led me to look into a solution to this to better safeguard people."
The devices were funded by local companies Bristol Water and Wessex Water.
Stuart has already been contacted by police forces across the country keen to roll out a similar scheme.
There are currently around 900,000 people in the UK living with dementia, according to the Alzheimer's Society, but that figure is predicted to rise sharply to 1.6 million by 2040.
The charity's policy manager, Gavin Terry, says with numbers on the rise there's a need for new ways to support people.
"Innovative technology, like this initiative, is really important in helping to do that," he says.
"It's also a really good example of how what's found currently in everyday technology can be put to good use in terms of helping to keep people safe, help their loved ones, support them and look after them, improve their wellbeing, and in many cases help prolong their independence.
"There are some ethical considerations. And there should always be some really clear guidelines around how this kind of technology is used, particularly for people who are lacking capacity to make decisions for themselves."