Pope Francis has surprised 20 former prostitutes by popping in for a visit at their safe house in Rome.
The women had been rescued from their pimps and are being given shelter and protection at an apartment run by a Catholic charity in Italy's capital.
The pontiff chatted to the women, some trafficked from Africa and elsewhere in Europe, for more than an hour.
The 79-year-old cleric has repeatedly described human trafficking as a "crime against humanity".
The Pope sat down with the women, including seven Nigerians, six Romanians and four Albanians, and listened to their stories of forced prostitution, the Vatican said.
The other three in the group came from Italy, Tunisia and the Ukraine.
They were all aged about 30 and had "suffered serious physical abuse" and now lived under protection, the Vatican said.
Promising women jobs, traffickers bring them to Italy and other western European countries but then force them into prostitution.
Pope Francis encouraged the former sex workers "to be strong" as they started their new lives with the help of the Pope John XXIII Community.
The unannounced visit to the prostitutes came under what the Vatican terms the Pope's "Fridays of Mercy", focusing on communities that have experienced suffering.