Knowledge base

We try to offer as much material online as possible, as we want to contribute to a safer environment for everyone.

Additionally, some information found on this page is meant for those who have already done a self-defense course with us, as an extra reminder of the covered material during the course. This information is not meant as a replacement of the full professional course.

View our Youtube channel as well!

Threat Recognition Trainer (TRT)

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Threat Recognition Trainer (TRT)
The Threat Recognition Trainer is meant to help you recognize "Pre-Incident Indicators" (PINs) faster and more efficiently. Threat recognition is a powerful tool to prevent violent encounters!

Background scenario of the TRT:
You are walking across the street, you are heading for a store. The neighbourhood is familiar to you, you have passed it a couple of times when it was quiet before. While you are walking, you briefly glance to your right.

Whatever it is that you see during the brief glance will determine your response:

  • "Yellow": you keep walking, there is nothing going on
  • "Orange": you start walking slightly slower in order to make a better assessment of the situation
  • "Red": you can see that there is danger, you backoff a little or start to de-escalate the situation
  • "Black": preventing the violence is no longer possible, you attack pre-emptive or run away

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View the frequently asked questions.

Frequently asked questions


What is the aim of the TRT?
To train your unconscious (automatic) threat perception by attentional retraining.

What should I do?
In the TRT, first select a display time (you should start with 3 seconds). Start by pressing "Go", now pay attention to your screen. A picture will be shown on your screen: it is your job to make a quick threat assessment. How dangerous is the situation? Judge the danger of the situation by clicking on "yellow", "orange", "red" or "black". When in doubt between 2 conditions, pick the lowest of the two.

Try to keep an eye out for Pre-Incident Indicators. For a list of some potential Pre-Incident Indicators, click on the diagram below.

How does it work?
The TRT is a form of attentional retraining, it is designed to help you become aware of PINs. A similar training method has been used by Paul Ekman for the detection of micro-expressions (as made famous by the TV series "Lie to Me").

First, play through the TRT at the slowest speed (3 seconds) so that you can consciously attend to PINs. If you are correct 8/10 times, then move to a faster speed. Keep doing so until you can get a 8/10 score at one of the higher speed settings (1/4th of a second or faster): this means that all you need is a glimpse to reliably detect PINs.

I do not agree with YOUR assessment of the situation.

Perfectly normal: threat assessment greatly depends on context, which is severely lacking in the TRT. Therefore, it is likely that you will encounter pictures of scenarios that we found more (or less) threatening than you. Does this make the TRT less effective? Not at all: the important part is recognizing PINs. Whether that puts you in condition "orange" or "red" is a detail compared with whether or not you spot or miss the PIN altogether.

Exactly what do the 5 conditions ("white", "yellow", "orange", "red" en "black") mean?
Let's explain using an example. Suppose you are walking on the street, and are approaching 2 men who are standing still.

Condition white would mean that you haven't even noticed them, because you are completely unaware of what is going on in this moment of your life. This is often caused by distraction, and it's neither any good for safety reasons nor for living a happy life.

Condition yellow would mean that you have noticed them due to a general awareness, but that you stay relaxed and continue walking.

Condition orange would mean that you've noticed that something is not right, and either slow down or stop completely to take a second look.

Condition red would mean that you've noticed a threat, and decided to walk away or to start de-escalating. In condition red, your hands should be up to protect against a sucker punch.

Condition black would mean that a physical confrontation is imminent (and de-escalation would be of no use). In condition black, you should either run away as fast as you can or attack the attacker(s).

Why Pre-Incident Indicators?

Lucky for you, we have put a video on our youtube channel covering exactly this topic. Watch the video explaining the importance of PINs now!

Will this make me paranoid?
This topic is also covered in the video above. So no, we don't believe the TRT will make you paranoid: it will help you distinguish a dangerous situation from a safe one.

Still, you probably shouldn't overindulge. Play the TRT on 5 different days in 3 minute sessions. After this: stop.

How do I provide feedback?

Feedback is greatly appreciated! Please send any problems, comments, or advice to:
If your feedback concerns a picture, then please send a link to the picture in your e-mail.


The information displayed here is meant only as a summary and not as a replacement of an actual self-defense course. The videos will open in a new window.

Pre-Incident Indicators (PINs) Awareness Videos:

Short Summary of our Self-Defense System:

Recommended Literature

A short list of recommended literature:

  • The Gift of Fear - Gavin de Becker
    In our opinion the best book on preventing violence, a must read!
  • On Combat and On Killing - Lt. Col. Dave Grossman
    Excellent books that illustrate what happens to the human body once it goes into survival mode.
  • Verbal Judo - Dr. George Thompson
    Very useful for those who want to further improve their verbal and de-escalation skills.
  • Warrior Mindset - Michael J. Asken, PhD., et al.
    Great book for mental toughness skills for warriors, mostly based on ideas about human performance in sport psychology.
  • The Emotional Brain - Prof. Dr. Joseph LeDoux
    In-depth information on emotions, specifically fear. The book describes the newest scientific knowledge in easy to understand language.
  • Why Zebra's Don't Get Ulcers - Prof. Dr. Robert Sapolsky
    Probably the best book available about stress, and the effects of stress.
  • Thinking fast and slow - Prof. Dr. Daniel Kahneman
    Extensive information on 2 separate mental system. One is quick and instinctive, the other slow and rational.

Other Recommendations

A short list of other methods and websites that we can recommend.

  • Explosive Self Defence (ESDS) - International Police Defensive Tactics Association (IPDTA)
    For those who want to learn more about self defense and master the open hand method.
  • SPEAR system - Blauer Tactical Systems
    Especially interesting for those who want to learn more about flinching and the first second of a fight.
  • - Richard Grannon
    This website is especially interesting due to its information on combative psychology.
  • Senshido - Richard Dimitri
    This style has perfected the use of claws (they call it 'the shredder') for self defense.
  • - Marc 'Animal' MacYoung
    Many interesting ideas on fighting and self defense, based on years of hands-on experience with violence.
  • - Low Tech Combat
    Provides information on self defense and topics around self defense, such as pre-incident indicators or legal issues surrounding self defense.
  • Adaptive Self Defense - Gus van Helvoirt
    Excellent weekly training in self-defense and combatives, localized in Eindhoven (the Netherlands).
  • Mosaic Threat Assessment System - Gavin de Becker
    A computer system that can help with recognizing danger levels. Can be used in situations like stalking, domestic violence, aggression at work or intimidation at a school.