Mechelen is halfway between Brussels and Antwerp. The city center is characterized by gabled Renaissance houses, carefully restored, while the marketplace is dominated by the Gothic cathedral on one side and the town hall, also Gothic, on the other. This is where the mayor of Mechelen, Bart Somers, has been waging his fight against extremism and radicalization since 2001. It's a fight he can never conclusively win, but that doesn't deter him.

Somers has a firm handshake. The 53-year-old is used to pressing the flesh. He's not only the mayor of Mechelen but also the parliamentary party leader of the Flemish liberals and the former premier of the region of Flanders.

Somers describes his politics as having two strands, or "legs."

"The 'right' leg is security. We've invested very heavily in the police," he says. "There's also no other city in Belgium with so much CCTV surveillance."

The "left" leg is his concept for integration: "We can't allow a social group to cut itself off or become isolated. All of us living here are Mecheleners, regardless of whether we were born here or in Morocco. We're not a flower-power city, either, though."

Island of happiness?

A comparison with the other cities in the region indicates that Somers' course is the right one. The attack on the Bataclan concert hall in Paris was carried out by terrorists from Brussels, one of the attackers on the Ramblas in Barcelona was active as an imam in Vilvoorde, not far from Mechelen, and just last year nine members of a terrorist cell were arrested in Antwerp.

Mechelen has no such problems. The city is seen internationally as an exemplary model of the successful integration of immigrants in general and refugees in particular. There are no Islamist radicals here; none of the city's 86,000 inhabitants have gone to Iraq or Syria to fight.

By way of comparison, 28 have traveled there from Vilvoorde, which is only half the size, while 200 have gone from Brussels. This is despite the fact that social conditions in Mechelen could be seen as very challenging: One in two children has an immigrant background. Twenty percent of the population is Muslim. People from 138 different countries live in the city.

In the 1990s Mechelen was still referred to as a "blot" on the Belgian landscape. It boasted numerous negative records: dirtiest city, city with the highest crime rate, bastion of the right-wing extremist party Vlaams Belang. Today, Mechelen is dubbed "The Pearl of Flanders," and Vlaams Belang got less than 9 percent of the vote in the last election. The city is clean, safe and one of the fastest-growing in the country. How was this turnaround achieved?

Step one: Learn the language

Somers believes the teaching concept of "incentives and demands" can also be applied to social coexistence. "If someone feels they're being taken seriously, they will make an effort," he says.

One place where they're making an effort is the Busleyden vocational school, an unassuming functional building right next to the cathedral. Eighty percent of students there have an immigrant background. They include 20 refugees, who have been divided up into three classes and are learning not only Flemish but also on how to get along in Belgian society. How do men and women behave towards each other in Belgium? What are the names of the country's towns and cities? How do you ask for directions?

If you drop in on these lessons, the first thing you notice is how empty the classroom seems. It could easily fit 35 students – but there are only eight students and one teacher, because the number of participants is limited to 12 per class. The aim is for the refugees to be able to join regular school classes as quickly as possible. Four out of five students manage it after one year – even though some have never even seen the inside of a school before.

Furthermore, on their first day every refugee is assigned a "buddy" who helps him or her get to grips with their new environment. "This is very important for the refugees, because that way they step outside their existing communities," Somers explains.

Last year, Mechelen was the only municipality in Belgium to volunteer to take 250 refugees. "The government said we didn't have to take anyone because there are already so many migrants living here. But we did it anyway. Just 15 years ago, we couldn't have done that; the people of Mechelen would have killed me."

Mechelen's 'ghetto schools'

"I like Mechelen a lot," says 15-year-old Rafig, who fled to Belgium from Afghanistan 18 months ago. "The only thing that bothers me is that I can't attend ordinary lessons yet." In the past Rafig would probably have been sent to one of Mechelen's migrant "ghetto schools" as soon as his Flemish improved. These days there are no more "ghetto schools," because Mayor Somers fought for a better mix of students.

"Initially, parents were concerned because the children at these schools often didn't speak Flemish very well, and as a result the quality of the lessons wasn't very high," he says. "We persuaded a few hundred middle-class families to send their children to one of these schools. And in return we, the municipality, guaranteed that the teaching would improve. That's good for the children, too, of course, because they're already living in tomorrow's reality: diversity."

Somers' initiative has also gone down well in Mechelen; he's been re-elected three times since 2001.

Investing in the future

The mayor sees the cost of the integration program as an investment in the future. He's financing this investment by making savings in other areas. "You just have to make good decisions and implement them systematically," he says.

Somers has reduced staff costs in the municipal budget from 65 to 39 percent, in part through redundancies. But the investment is paying off. The mean local income is rising faster than average, and Mechelen is the only Belgian city where the poverty rate is falling.

This upswing is contributing to the fact that more and more high-income families are moving to Mechelen, and the tax income is having a noticeable effect on the city coffers. This in turn benefits all those who live in Mechelen – regardless of whether they've been there for a few days or since birth.