Learning from Brexit: Seven killer mistakes to avoid in your important negotiations

Article by Ken Thompson, last updated May 2019

Whether you are a "Leaver" or a "Remainer" the UK approach to negotiating Brexit, led by Prime Minister Theresa May,  can teach us some very important lessons about effective negotiating techniques.

One of most successful approaches to negotiation is known as principle-based or principled negotiation made popular by the book “Getting to Yes” by Roger Fisher and William Ury  which is the definitive text on modern negotiation practices. 

Using “Getting to Yes” as our guide there would seem to be at least 7 basic mistakes in the approach the UK adopted to its Brexit negotiations with the EU:

Mistake 1: Don’t tell everyone up front what a tough negotiator you will be

By all means tell your sponsors you will be passionate in looking out for their interests but don’t boast about so much that the other party get to hear about it otherwise you will set up a Win-Lose dynamic which will only harden your partner's position. 

Mistake 2: Don’t demonise the other party in the negotiation

It is OK to say upfront that it will be a real challenge to find common ground with this negotiating partner. But governments can even collaborate with terrorists in the public interest (e.g. to agree codes to distinguish real threats from copycats) so common ground is almost always there if you are prepared to really look for it. But like the previous mistake don’t make the other party into The Enemy – it will just unnecessarily eliminate some  the flexibility or wiggle-room you will have available to you.

Mistake 3: Don’t constantly threaten “No Deal”

Best practice in negotiation says that you should always have a BATNA – a “best alternative to a negotiated agreement”. However "Getting to Yes" clearly states that you should NOT use your BATNA to bully or threaten the other party in the negotiation as it destroys the trust with the other party who may start weaponizing their BATNA against you!

Mistake 4: Know your weaknesses and don't give away your power

If you do a SWOT Analysis on any two sets of negotiating positions one of the important factors is whether either of the parties are working against a hard deadline. As such a deadine approaches their need to deal progressively becomes greater than the other party. Early invocation of Article 50 before formulation of a solid position limited the UK power in the negotiation. Your SWOT Analysis should also determine whether both sides need to deal and if one side needs a deal more which is another positional weakness or threat that you will have to try and mitigate against in your negotiating strategy.

Mistake 5: Sort out ambiguities and problems in your own position first

This is a biggie. A classic anecdote in good negotiation is the orange story in "Getting to Yes". A husband and wife both want an orange but they only have one between them. If they negotiate in a Win-Lose way they will split the orange in two. The authors note that in Win-Lose negotiation you often end up in a compromise which suits neither party. However, if the couple negotiate collaboratively they will discover that the woman wanted the orange peel to make jam and the man wanted to eat the orange fruit. Thus they can find a Win-Win position.  The UK solution to Brexit was a compromise between Leaving and Remaining. This could have worked (see Mistake 7) but because it was perceived as imposed rather than co-invented it lost both groups of stakeholders. Both sides felt it was a BINO (Brexit-in-name-only) which delivered neither of their key (conflicting) objectives – a close on-going relationship with EU versus a clean break with the EU. A major contributing factor was the emergence of this compromise so late in the day and with the EU perceiving it as a "done deal" (Mistakes 4 and 6).

Mistake 6: Know your Negotiating Partner

I could have titled this "know your enemy" but, of course, the other player is not your enemy but your negotiating partner (see Mistakes 1 and 2). You need to understand who else your negotiating partner needs to involve on their side to review proposals and reach agreement. In Brexit the UK clearly did not really fully appreciate the processes the EU would need to use to keep its 27 key stakeholders in the loop and the constraints they were operating within. 

Mistake 7: Don’t lose the confidence of your sponsors/stakeholders 

Due to a lack of engagement and consultation the trust of the UK government's stakeholders (i.e. parliament) was strained, stretched to breaking point and then lost. Parliament then started to take back control from the UK negotiating team to try and interject themselves as a new party in the negotiation process. The consequence was a severe loss of power for the UK negotiating Team leaving the EU wondering whether they were dealing with “the monkey or the organ grinder”? The lesson is that if you do not proactively and sensitively manage your stakeholders then they may start managing you!


I could continue with other lesser mistakes such as trying to reopen a “done deal”, but I think these seven points are sufficient for a useful checklist for your next important business negotiation:

  1. Don’t tell everyone up front what a tough negotiator you will be
  2. Don’t demonise the other party in the negotiation
  3. Don’t constantly threaten “No Deal”
  4. Know your weaknesses and don't give away your power
  5. Sort out ambiguities and problems in your own position first
  6. Know your Negotiating Partner
  7. Don’t lose the confidence of your sponsors/stakeholders 

FINALLY, taking a lesson from aviation and practising (or war-gaming) your negotiation scenario in a safe environment BEFORE you try to do the real thing is also a very sensible idea.

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Ken Thompson

Ken is a practitioner, author and speaker on Leadership, Collaborative Working, High Performing Teams, Change Management, Project Management and Business Acumen. His work has featured in major publications including The Guardian , Wired Magazine, The Huffington Post and The Henry Ford Magazine. Ken has also spoken at many international events including TEDx, the Institute for Healthcare Improvement (IHI), Learn Tech (London) and NASA.

Ken is Founder of Business Simulations Ltd.

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