Dealing with aggressive power-based negotiators is one of the most common challenges many people struggle with in the process of negotiation. There are a few things to be aware of when squaring off with such people that can help you keep your cool and hold your ground so that you get your needs and interests respected without giving in.
First, they like conflict and confrontation – it is their comfort zone – and about 90% of us on the western world are what psychologists call “conflict averse”. Power negotiators will take advantage of this, creating chaos and then exploiting our weakness as we struggle to keep our emotions under control. So the first thing you need to do has nothing to do with strategy or technique – but mindset and emotional intelligence. You need to get comfortable with conflict and learn to stay centred while things are being thrown at you that are designed to cause stress. Being able to stay unaffected by aggressive pressure tactics is powerful – it is unsettling for the other party that is trying to gain advantage.
Aggressive negotiators can also be highly intelligent people. They can throw some very persuasive arguments at you as to why you should agree with what they want. So you need to be able to respond with some effective well thought out responses that can counter their demands while advocating for what is important to you.
Thirdly, these negotiators can also be intuitive and perceptive enough so that they can quickly get a sense of weaknesses and vulnerabilities in others and can exploit these in a negotiation situation. Lastly a small percentage of these people have a flexible ethical compass that in their minds means the end justifies the means. They can be willing to be unethical and utterly ruthless to achieve their goals.
Any one of these attributes can be challenging to deal with. If you encounter all of these characteristics in one person – you can have your hands full.
Tips on dealing with aggressive and Power-based negotiators

1. Get comfortable with conflict and work on your confidence – if there is no conflict it is not a negotiation, it’s a conversation. Recognize that negotiating style is really learned behaviour and power-based negotiators can be influenced to be more collaborative with the right leverage. Conflict is uncomfortable but sometimes it hurts more to avoid it.

2. Do your homework – preparation is always important but with aggressive negotiators it is critical. Find out everything you can about that individual and their negotiating tactics, talk to people who have dealt with them if you can, look at the results of deals they have negotiated in the past and develop a profile of that person. Every person and organization has strengths and weaknesses – you just have to find them.

3. Develop a strategy – based on your research prepare an effective opening to set the tone and direction of the interaction, try and identify positions and interests around each of the issues, understand your leverage points and concession strategy, and know your BATNA so that if necessary you have the option to walk away. The basic approach is to block or neutralize the power of an aggressive negotiator and respond with counter proposals that lead to more constructive interaction.

4. Win their respect early. This is key – you might have to get confrontational (they respect people standing up to them), you might have to use reason (an argument or proposal that makes sense and has real value will get their attention), but stay calm in the face of any test they throw at you and you will win the right to engage them in a direct negotiation where you can get something done. If you fail here the rest of the negotiation will be much more uncomfortable and difficult.

Trudeau and Trump – Insights on dealing with Power-based Negotiators:
Financial Post: How To Negotiate with President Trump

Trudeau Trump Meeting – Insights broadcasted from CBC News Desk:
CBC News Network – Trudeau Trump Meeting