The point is that currently "There is no specific criminal offence of domestic violence. Instead, a definition that refers to "incidents of threatening behaviour, violence or abuse" was adopted in 2004.
Ministers say that has led police and prosecutors to make too narrow an interpretation of the term and let some perpetrators off the hook."
The point of is that bullying, verbal and emotional abuse and controlling/coercive behaviour will be defined as domestic abuse and could lead to criminal prosecution if it amounts to harassment.
Physical assault will still be assault, and will still be a criminal offence.
As Chief Constable Carmel Napier, of Gwent police, said: "The amendments to the definition are key in helping to raise awareness and enable effective prevention working in partnership with all agencies.
"Domestic abuse ruins lives. In some cases it ends in homicide. This amended definition will help us all to work together to defeat this dreadful crime."
It's about raising awareness of the seriousness of the behaviour, and intervention before people get beaten up and murdered.
It isn't perfect, and change isn't about to happen overnight. But it's a start. At last.