Apply these techniques with your boss, a customer, a family member, even a stranger. These approaches may feel unnatural at first, but they work. 

When dealing with an unreasonable person, the fear response part in your brain (fight-flight-freeze reflex) is activated. This brain region can’t distinguish between a customer yelling at you or a vicious dog that's about to attack you. 

It’s up to you to engage your conscious intention to defuse the situation. 

1. Listen. Listening is the number one step in dealing with “unreasonable” people. Everyone wants to feel heard. No progress can take place until the other person feels acknowledged. While you’re listening, really focus on what the other person is saying, not what you want to say next.
2. Try and understand a difficult person and try to put yourself in their position. No matter how absurd it sounds, understanding their issues and problems might help you realize how to approach them and establish better communication. Make eye contact, establish rapport, clarify all the essential things, paraphrase all the crucial points they make during the conversation. Once you genuinely hear what they are saying, it will be easier for you to understand why they behave the way they do.
3. Don’t argue or try to convince the other person of anything.
4. Repeat your point of view. It can be frustrating when the difficult person doesn’t seem to listen to what you have to say. If an unreasonable and oppressive individual ignores what you say, address them directly, repeat your point, and ask them what their opinion is. Don’t give up, even if you have to repeat it a couple of times. By showing them that you want to have your say, you’ll appear confident and competent.
5. Stay calm. When in an emotionally charged situation, it’s easy to get caught up in the heat of the moment. Monitor your breathing. Try to take some slow, deep breaths.
6. Ensure you take turns communicating. In healthy communication, participants should ideally take turns in leading and following. When dealing with an aggressive person, they’re trying to impose their plan and expect that you’ll follow them. Domineering people set a negative tone and focus on the negative. Introduce a new point of view and offer a solution to the problem. This proactive attitude is constructive and puts you in charge of the discussion.
7. Don’t demand compliance. For example, telling someone upset to be quiet and calm down will make the other person angry. Instead, ask the person what they are upset about—and allow them to vent.
8. Saying, “I understand,” usually makes things worse. Instead, say, “Tell me more so I can understand better.”
9. Look for the hidden need. What is this person trying to gain? What is this person trying to avoid?
10. Find others around you that might be able to help. If you’re at work and there’s an angry customer, quickly scan to see if a colleague can assist.
11. Misunderstandings and high expectations inevitably lead to conflicts. Discuss and divide up your responsibilities so that you can reduce unrealistic expectations and forestall conflict.
12. Don’t act defensively. You’re naturally not enjoying the other person saying nasty things or things you know aren’t true. You’re going to want to defend yourself. But the other person is so emotionally revved up, it’s not going to help. Remember, this is not about you. Don’t take it personally. (I know, easier said than done.)
13. Don’t return anger with anger. Raising your voice, pointing your finger, or speaking disrespectfully to the other person will add fuel to an already heated situation. Use a low, calm, even monotone voice. Don’t try to talk over the person. Wait until the person takes a breath and then speaks.
14. Keep extra space between you and the other person. Your instinct may be to try to calm the other person down by putting your arm on theirs or some other similar gesture that may be appropriate in different contexts.
15. Apologizing is not a good strategy. Saying, “I’m sorry,” or, “I’m going to try to fix this,” can go a long way toward defusing many situations.
16. Set limits and boundaries. While some of the above tips have encouraged listening and letting the angry person vent, you also have the right to be assertive and say, “Please don’t talk to me like that.”
17. Trust your instincts. If your gut is saying "this is going downhill fast", be ready to do what you need to do to remain safe. Look for an exit strategy.
18. One response does not fit all. You have to remain flexible. Although these guidelines have proven effective in de-escalating challenging situations, every person is unique and may respond differently.
19. Don’t judge. You don’t know what the other person is going through. Chances are, if a person is acting unreasonable, they are likely feeling some vulnerability or fear.
20. Reflect respect and dignity toward the other person. No matter how a person is treating you, showing contempt will not help productively resolve the situation.
21. Debrief. After the situation is over, talk to someone about what happened.
22. Discharge your stress. You had to put your natural reactions on hold for a while. Now is the time to discharge some of that pent-up adrenaline. Go for a run. Take your dog for a walk. Don’t let the emotions stay in your body.