Harald Weilnboeck has worked for years in Germany as a first-line practitioner trying to discourage young people from joining violent right-wing extremist groups or help them distance themselves from neo-Nazi organizations they'd previously joined.
Now, with more young Europeans being recruited as foreign fighters by Al-Qaeda or the militant group Islamic State (IS), Weilnboeck finds the work focusing increasingly on individuals attracted to Islamic extremism.
When it comes to working face-to-face to deradicalize young people, Weilnboeck says there is little difference between the methods used with neo-Nazis and with foreign fighters from IS or Al-Qaeda.
"On the level of methodology and how you engage with the person -- be it one-on-one or be it in small groups, which I would prefer -- the principles of work seem to be pretty much the same," Weilnboeck says.
"I remember us coming from the work with neo-Nazis, right-wing extremists, and wondering, 'Well, could we do pretty much the same thing or we would have to invent something particularly new for people who come from Al-Qaeda or IS backgrounds?'" he tells RFE/RL. "In fact, you have to deal with male or female psychologies that resemble each other."
As the co-chairman of the working group of the Radicalization Awareness Network, a European network that brings together government and nongovernmental organizations working to keep young people away from violent extremism, Weilnboeck is now helping to draft guidelines on the lessons learned by hundreds of practitioners with first-hand experience in what are called "exit programs."
Most programs differ from each other and are adapted to different local, political, and cultural settings.
That makes them difficult to compare, or to point out any single program that is undisputedly more successful than others.
But Weilnboeck says successful programs tend to deal with radicalization as a psychological process -- and thus involve counseling that addresses deep psychological issues. That means working in ways akin to psychoanalysis in order to identify the root causes of anger that attracted young people to violent extremism in the first place.
A successful exit program also recognizes there are differences between dissuading someone from committing acts of violence and actually changing a person's underlying belief system, which is much more complicated.
Weilnboeck says a "principle of trust-based work to establish a climate of trust" is vital.
"The principle that seems to be key is that you need to engage in a quite personal -- not private, but quite personal -- relationship-based interaction," he says. "That actually means that you need to be able to respect the person that you are working with and be without prejudice and open to interacting with this person on an individual personal level, while also being ready, if necessary, to confront certain attitudes that you're going to run into. [It's] the principle of trust-based work to establish a climate of trust."
Involving a former member of an extremist group can be helpful in building credibility and has advantages, but Weilnboeck says it "tends to be overrated."
He says it is more important that first-line practitioners have "skills of a therapeutic kind."
For that reason, he advises that professionals with experience in psychological counseling or social work -- including youth workers or family workers -- need training to deal with violent extremists.
Weilnboeck also advises policymakers that the best role for governments is to stay out of direct counseling and focus, instead, on funding independent "facilitators."
We were blindfolded by our conventions of seeing extremism as a product of male violence. That is not true. Extremism is very much a systemic thing in which women have been involved -- always."
"If your first goal is to establish trust, you must make sure that the facilitators are not people who are directly employed by the state and obliged to report back on the person," he says. "It's better if they come from nongovernmental organizations or are independent and offer assurances that their conversations are confidential and won't be relayed to authorities."
"You must not forget that you're dealing with a group of young people who are extremely distrustful -- distrust to the point of conspiracy theories and an outright paranoid way of looking at the immediate environment."
Weilnboeck says one lesson successful facilitators have learned is to avoid engaging in debates about politics or religious doctrine with those they are trying to deradicalize.
He says such debates usually fail to alter the belief system of a violent extremist, especially in the early stages of a deradicalization program, but will almost certainly foster distrust.
Another key lesson Weilnboeck and his colleagues have learned is that gender-based issues are critical when dealing with both right-wing extremists and Islamic militancy.
"Just check the issues of sexism and homophobia in the Islamic [extremist and neo-Nazi] context," Weilnboeck said. "It's just very clearly there. You'd better not be gay and you'd better fulfill your feminine role in a very restricted way."
"You'd be surprised that if you engage with issues of gender in talking with the young people, how effective that can be and how much more effective that is than talking ideology or religion," he says. "We've become aware that violent extremism is both a male and female issue, very strongly."
"It took us some time," Weilnboeck confesses. "We were blindfolded by our conventions of seeing extremism as a product of male violence. That is not true. Extremism is very much a systemic thing in which women have been involved -- always."
"So do make sure that you also work with women and girls," he continues. "And make sure that you work with the young people on their personal concept of being a male or being a female, because you'll find in these concepts everything that is driving violent extremism itself. There is no violent extremist that is not also a sexist or homophobic. And that counts for men and women."
He says a successful deradicalization program takes a long-term commitment -- with regular sessions lasting at least six months and often stretching out longer than two or three years.
Making matters more difficult is the issue of how to measure success.
"As a practitioner, you have certain intuitions about whether the process is productive," Weilnboeck says. "I would go by criteria of a narrative in-depth exchange. Is it there or is it not there? What is the level of hesitance on the other side?"
One method that Weilnboeck insists does not work, but which continues to have many supporters, is the idea that the Internet and media programs can be used to deradicalize violent extremists.
"The idea that the Internet, because it seems to be a prime factor of the problem, also needs to be a factor of the solution is entirely erroneous," Weilnboeck insists. "That is a true fallacy which you see policymakers all over Europe and the world believe in."
"The processes of deradicalization actually rely on a direct interpersonal relationship placed in a confidential setting where individuals have names and can actually be identified and then directly interact -- face-to-face. Videos cannot deradicalize anyone."