Step One: Initial contact - police take details on what prompted an enquiry and the nature of a relationship before running initial checks and a risk assessment.
Step Two: Face to face meeting - to gather more information. Police may run checks with other agencies including the prison service, the probation and social services.
Step Three: Multi agency meeting - police meet other safeguarding agencies (such as the probation service, prison service, social services). They decide whether disclosure is lawful, necessary and proportionate to protect a person.
Step four: Potential disclosure - if checks show a record for abusive offences or disclosure would prevent further crime, the police may disclose information to protect a potential victim.
A scheme which allows people to approach police to find out if their partner has a history of domestic abuse is to be rolled out nationwide, ministers are expected to say later today.
Four police forces successfully piloted "Clare's Law", which allows concerned men and women the right to ask police if their partner has a history of domestic violence.
Forces in Gwent, Wiltshire, Greater Manchester and Nottinghamshire have been running the scheme since the summer last year and ministers are today expected to tell Parliament that it should be extended.
The law is named after Clare Wood, who was strangled and set on fire in 2009 by her boyfriend, George Appleton, who had a history of violence against women.
Candles will be lit at Llandaff Cathedral to mark White Ribbon Day, a campaign raising awareness of domestic abuse.
The campaign is being supported by Welsh Women's Aid who say, across the world, domestic violence causes more deaths to women than malaria, cancer, traffic accidents and wars combined.
Figures from Wales Violence Against Women Action group show that every year seven women die at the hands of their partner and 50,769 women will experience a total of 203,075 incidents of domestic abuse - but there will only be 3,385 convictions.
Local Government Minister Lesley Griffiths will visit the cathedral and an information centre in Newport to show her support of the campaign.