Every year more than a million people are victims of domestic abuse in the UK. Often the focus is on helping the victim find safety - but what of the abusers? Should they be given help? And can they change?
Andrew found himself wanting to change when he faced the prospect of losing his family.
He had been abusive to his partner, Emma, injuring her a number of times.
After his violence escalated, he moved out and Emma struggled to cope with their children.
They were later removed from their care.
Emma was offered courses to support her as she tried to move on from the abusive relationship and rebuild her self-esteem.
However, Andrew was looking for something for himself.
He wanted to stop abusing his partner and sought help. He found Phoenix Domestic Abuse Service, which offered a weekly programme to help men confront their actions and change their behaviour.
Andrew remembers his first time at Phoenix, walking into a room full of "big blokes, mean looking blokes" and thinking "Oh, what have I done?"
But after seven months on the course he has formed a bond with the group and says he is beginning to understand the effects of his behaviour.
Every week he was challenged on his behaviour and had to confront his actions.
The course uses role-play, problem-solving tasks, and challenging discussions to teach the men about the impact of their actions.
"I'm not proud of who I was then, but I am proud of who I am now," he says.
Emma says she recognises the transformation in Andrew.
"He's different. We talk more, he listens," she says.
They were separated for two years but are now together again and are working to get their children back.
Lidia, who helped Andrew through the course, said it is important to intervene because "if no one does any work with that person then they are likely to go on and find another victim.
"Their next relationship is likely to become abusive."
Phoenix sees both sides of abusive relationships on a weekly basis, believing the abuser and the abused partner both need support - either together or apart - if they hope to break out of the violent cycle.
'Seriously bad violence'
But not everyone has such positive experiences of domestic abuse courses.
Sarah - not her real name - did not see any change in her partner when he was referred to a programme by her local authority.
"If anything it made him angrier," she says.
The abuse continued, both throughout and after the course.
"[It was] seriously bad violence," she says. "Strangling you, picking you up by your hair, throwing you across rooms, smashing your head into walls."
She thinks the courses are not enough to make meaningful change and abusers will only reform with years of therapy.
"Their whole brain needs unpicking. It's got to be long-term mental health intervention, not a six-week course, because they are so manipulative they will pull the wool over people's eyes."
She says she feels let down by the system.
She has not been offered any significant support to protect her from her abusive partner, she says, adding that he knows where she lives and continues to harass her and her children.
She doesn't feel the perpetrator programme held her abuser to account.
It is estimated that every year more than 3,000 people in the UK attend such courses - and that number is growing each year.
Cafcass, the Family Courts Support Service, made 800 referrals last year, four times as many as five years ago.
The vast majority of those who attend are men.
Cycle of violence
Costs start at around £500, with that figure being picked up by either local authorities or individuals.
Some courses target the perpetrator alone, while others run parallel courses for their partners. However, the debate rages as to which approach works best.
Dr Gene Feder is conducting the first clinical trial of a perpetrator course.
"If you ignore perpetrators you're really ignoring the upstream origin of the problem," he says.
"If you just respond to survivors you're in some ways colluding in the repeated cycle of violence which goes on."
Rachel Williams is a survivor of domestic abuse, she was with her husband for 18 years and the abuse she suffered escalated over time.
When they separated he came to the salon where she worked with a sawn off shotgun and shot her in the leg at point blank range.
Rachel is now an advocate for survivors and hears from lots of women seeking support.
She has heard of abusers using the courses in court to claim they have changed, despite continuing to abuse and manipulate their partners and even blaming their partners for having to go on a course.
She thinks people do not understand the true effect of domestic violence and how clever and manipulative abusers can be.
"We need to keep monitoring them. The only people who can tell if they have changed is their new partner."
Denise has been running a perpetrator course for more than 20 years.
She says those who want to change should be given the opportunity to do so.
"There are going to be some people out there who cannot change and will not change, for a variety of reasons.
"But those that want to, those that are willing to give it a go, they need to be given the opportunity and I think for those people, yes they can change."
Watch BBC Panorama's 'Can Violent Men Change' on Monday at 20:30.