New measures are set to come into force which hope to protect victims of stalking at "the earliest opportunity".
From Monday officers will be able to apply to magistrates for a Stalking Protection Order (SPO) - blocking alleged perpetrators from contacting or approaching their victims while a probe into their behaviour continues.
The measures have been introduced in a bid to take a tougher stance on stalkers.
SPOs would usually remain in place for a minimum of two years. Those who breach the civil order could end up behind bars for five years.
The move has been welcomed by campaigners but warn the measures will only be effective if action is taken quickly.
Clive Ruggles, whose 24-year-old daughter was murdered by her jealous ex-boyfriend, said the orders could have made a "critical difference" in his daughter's case.
Speaking on behalf of the Alice Ruggles Trust, he described the order as a "powerful new tool", adding it was "critical" there was no delay in arresting perpetrators who breach them.
He said: "Any other response may well escalate the risk to the victim."
As well as a ban on pursuing victims, courts could use the new ruling to force perpetrators to seek professional help and urgent cases could be fast tracked with an interim order imposed.
Katy Bourne, chairman of the Association of Police and Crime Commissioners and a victim of stalking, had to face court on her own to get a civil injunction in her case.
She said SPOs were a "breakthrough" and - if they had been in place during her ordeal - would have given her "peace of mind" and helped her "sleep at night".
She added, though, that they must be "properly enforced".
Conservative Party chairman James Cleverly told Sophy Ridge on Sky News, the measures will give more powers to police.
"What we know is a huge amount of people have to endure stalking, a much larger percentage than I think most people would realise. It's something no one should have to deal with.
"We want to give more powers to the police and to the courts and stalking protection orders is the vehicle we are bringing forward to do that.
"That will protect people and there have been occasions where people's lives have been taken by stalkers and we want to protect people from that."
Victoria Atkins, minister for safeguarding and vulnerability, said: "I am determined that we do everything we can to better protect victims and new Stalking Protection Orders will help the police to intervene and take action against perpetrators at the earliest opportunity."
It is estimated one in five women and one in 10 men aged 16 and over in England and Wales have experienced some form of stalking, according to a crime survey carried out on behalf of the Office for National Statistics.