By Anna Browning and Duncan Walker
Mehmet Goren, the father of 15-year-old Tulay Goren, has been found guilty of murdering her after she fell in love with the wrong man. Tulay's death serves as a "wake-up call" over the issue of such "honour killings", a jury at the Old Bailey heard.
Mehmet Goren collapsed in court when his wife testified against him
It was in January 1999 that Tulay was last seen. Her body has never been found.
She was killed by her father Mehmet after forming a relationship with factory worker Halil Unal.
The family, from a Kurdish part of Turkey, disapproved because of religious differences - Mr Unal was a Sunni Muslim, while Tulay's family were Alevis - and the fact that he was 15 years older than her.
The case was a "terrible reminder of what honour-based crime can involve", prosecuting lawyer Jonathan Laidlaw QC said in his closing speech.
"If there are those in this country who believe we do not face similar problems as those confronted by the Turkish authorities and other countries where honour violence occurs, then this case will be something of a wake-up call."
Tulay's case is far from being an isolated incident, however. Police believe that about 12 women a year are the victims of "honour killings" in the UK. Many more suffer violence.
Honour killings have mostly occurred in families of South Asian and Middle Eastern origin. None of the world's major religions condone honour-related crimes.
Two years ago the father and uncle of Banaz Mahmod, another woman from a Kurdish family, were convicted of arranging her murder.
And in 2003 Iraqi Kurd Abdalla Yones was jailed for stabbing his daughter Heshu to death because of her Western dress and Christian boyfriend.
In response to the case, the Metropolitan Police set up a strategic task force to tackle the issue.
Around 100 murder files spanning the last decade were reopened in an effort to find common links. One of the files was Tulay's.
"In every case we have looked at, there's always a conspiracy," said Commander Steve Allen, the Association of Chief Police Officers' lead on honour-based violence and forced marriage.
"There will be a meeting of the family, potentially involving other members of the community, to discuss and decide when the killing is going to be carried out, where, how and by whom," he told the BBC.
Tulay came from Elbistan, in a predominantly Kurdish area of Turkey
In Tulay's case, the Old Bailey jury also heard from Professor Yakin Erturk, a sociology professor at Ankara University and expert on "honour killings". She was the first to give expert evidence at a case of this kind in the UK.
She said it was only in the past 15 years that such killings had become a recognised problem in Turkey, although there are an estimated 200 cases a year.
Prof Erturk, who is also the UN's special rapporteur on violence against women, described a culture where a cousin slit a woman's throat in the street for requesting a song on a radio station.
Since Tulay's death 10 years ago, police have made "remarkable" progress, said Cdr Allen.
Officers are now taught to recognise the risks of "honour-based violence" from the moment a report is made.
There is an awareness that some victims may be taken abroad, that the risk of violence against other family members exists and that some families will go to considerable lengths to find those who "escape".
But the need to challenge "perverted" notions that a woman can compromise the "honour" of a family or community because she keeps the "wrong company", has a boyfriend or is "too Western" in her dress or appearance remains, said Cdr Allen.
"There's an absolutely crucial issue about the need for leadership within affected communities. There's no middle ground here, you either condemn these practices or you collude with them."