Every domestic abuse death is to be automatically reviewed in England and Wales in an effort to make sure lessons about violence in the home are learned.
Mandatory case reviews will now be carried out by all involved agencies, including police and health services.
It follows comments from Director of Public Prosecutions Keir Starmer that teenage women are most at risk of abuse and more must be done to tackle it.
Almost 100 women are killed by partners or ex-partners each year, figures show.
And 21 men died from domestic abuse in England and Wales last year.
Together with the police and health services, local authorities, probation, voluntary groups and any other bodies connected to a victim will now have to examine together exactly what went wrong and consider how to spot the signs when someone's life is in danger.
Speaking at the Crown Prosecution Service headquarters in central London on Tuesday, Mr Starmer said too many prosecutions were failing and more must be done to protect victims.
He also stressed the need for victims to be supported both during and after criminal proceedings.
He pointed to British Crime Survey findings which showed young women between the ages of 16 and 19 were most at risk of domestic abuse.
"What that tends to show is that there may be a next generation of domestic violence waiting in the wings.
"Domestic violence is serious and pernicious. It ruins lives, breaks up families and has a lasting impact," he said.
"It is criminal. And it has been with us for a very long time, yet it is only in the last 10 years that it has been taken seriously as a criminal justice issue.
"Although greatly reduced, the refrain 'it's just a domestic' is still heard far too frequently.
"The steps that we and our criminal justice partners are taking to tackle domestic violence risk limited success unless this complacency is tackled head on. A change in attitude is clearly needed."