Four people have been found guilty of trafficking women from Slovakia to Glasgow and forcing their victims into prostitution and sham marriages.
The women were transported to flats in the Govanhill area between 2011 and 2017, then exploited by the gang.
One victim was sold for £10,000 outside a store in the city's Argyle Street.
Vojtech Gombar, 61, Anil Wagle, 37, Jana Sandorova, 28, and Ratislav Adam, 31, denied the charges but were found guilty at the High Court in Glasgow.
They will be sentenced next month.
Police, who cracked the trafficking ring in a five-year operation dubbed Operation Synapsis, described the crimes as "despicable".
"It's a heinous crime," says Detective Inspector Steven McMillan, who led the investigation.
"It's horrific to think that people think it is acceptable to buy and sell other human beings as a commodity, to have no thought for the impact and trauma it is going to have on them."
He said the convictions were the culmination of a complex investigation involving law enforcement from around the UK and European agencies such as Europol and Eurojust.
Police first became aware of the trafficking and exploitation in 2014 but it took a three-year operation before about 70 officers raided four flats in the Govanhill area of Glasgow, leading to the arrest of Gombar, Wagle, Sandorova and Adam.
Gombar, who was described as the ringleader of the gang, had family ties with fellow Slovakians Adam and Sandorova.
They are ethnic Romani and came from the town of Trebisov in the east of Slovakia, near its border with Ukraine, from where most of the women were trafficked.
Wagle, from Nepal, became involved initially because he wanted to buy a bride.
Over the course of the investigation, police had helped more than a dozen suspected victims, aged between 18 and 25, to safety.
The women were trafficked to the UK, usually by bus and car, having been promised a better life and work.
But when they arrived they were sold for between between £3,000 and £10,000 as part of a sham marriage scheme.
The buyers were mainly men from Pakistan who wanted EU citizenship so they could live and work in Europe, and wanted the women to become their wives.
Some of the victims were used as prostitutes while others were abused by the men who bought them.
Police found that the women were held in "safe houses" in places including Manchester and Yorkshire before being taken to Govanhill.
Det Insp McMillan said the women had their identity documents taken from them and their movements controlled.
"Some of them suffered abuse, they were forced into sexual exploitation before being forced into sham marriages," he said.
During the court case, a 28-year-old woman from Slovakia said she had thought that she and her sister were leaving for jobs in London but she ended up in a flat in Govanhill with no job and no money.
She said she was forced to marry the son of a Pakistani man who had chosen her.
Another woman told the court she was brought over from her home town of Trebisov, when she was four or five months pregnant, "for a better life".
She was handed over to a Nepalese man outside Primark in Argyle Street in 2014 for £10,000.
The woman also claimed that prior to being sold, she was made to sleep with Pakistani men for money and described this as "hitchhiking".
The court also heard how one woman managed to escape and ran to a nearby shop where she raised the alarm.
The woman spoke no English and the shopkeeper could not understand her, but a beat police officer managed to translate with the help of two young girls who lived nearby.
The police officer said the woman wanted to get her identification documents and walked with her to the flat to retrieve them.
The officer told the court: "We got a phone number for her sister in London, and it was then we realised she had allegedly been trafficked to Glasgow."
Det Insp McMillan said all the women involved, most of whom are now back in Slovakia, were severely traumatised by what happened to them, which added extra complications to the investigation.
He said: "It is unbelievable in this day and age but, yes, women were being sold as a commodity in Glasgow."