The United States and the European Union were on the brink of a trade war less than 48 hours ago. As President Trump threatened to raise European car import tariffs to 25 percent, Europe considered $20 billion tariffs on American imports, in retaliation. 

Before the tit-for-tat escalated further, Jean-Claude Juncker, President of the European Commission and reputedly Europe's best deal-maker, boarded a flight to Washington in a "last ditch bid".

Hopes were low. Pessimism abounded, President Trump had only recently labelled the European Union a "foe".

And yet, hours later, President Trump and Mr. Juncker left the negotiating table as friends, each happy with the outcome. The trade war is averted, at least, for now.

These three tactics helped get both parties past the impasse. 

1. Bring the right food to the table -- at the right time.

Mr. Juncker's focus wasn't just on what Europe wanted. It was important to consider what the U.S. needed.

A change in trade relations with other nations has recently left the U.S. with a gap in the export market for soybeans.

Mr Juncker had the opportunity to offer a solution: Europe will import billions of dollars worth of soybeans from the U.S.

Had Mr. Juncker chosen another product with equal generosity -- or offered the soybean deal at a different time, the outcome might not have been quite as successful.

Your negotiating partner might tell you what they need.  If not, careful prior research will reveal what matters to them at this time.

By fulfilling a pressing need, you'll be doing them a favor they'll want to return -- or, at the very least, they'll think they made a big win so they can afford a small loss.

Either way, they'll be more likely to compromise. 

2. Cooperate, don't persuade.

Persuasion requires an alignment of ideas. Cooperation involves an alignment of outcome. 

If you try to sell your deal by persuading the other person to change a belief or idea, you threaten their self-identity. They will defend their self-identity by being hostile. 

If, instead, you base your negotiation on cooperation without persuasion, the other person will be far more open to compromise. 

Although the deal took place behind closed doors, it is likely that Mr. Juncker approached President Trump leaving core political beliefs aside.

Their focus was the deal in question, not political ideology. So they cooperated, without feeling persuaded. 

Making a negotiation about the outcome and never the person (and core-beliefs), inspires trust in both parties.

Even if one side doesn't get exactly what they want, or gives up a little too much, their self-pride stays untarnished. 

3. Frame your outcome inside common ground.

President Trump found the tariff disparity between the U.S. and the European Union unfair. Mr. Juncker did not want the U.S. to raise tariffs on cars from Europe. 

So they found a common ground: no tariffs. President Trump suggested this in a tweet prior to the meeting, Mr. Juncker confirmed this was his objective at the press conference after the meeting.

Of course, if both sides are aiming for no tariffs, it would be unreasonable to now raise tariffs.

So, Mr. Juncker got the deal he flew all the way over to get -- the U.S. will no longer be raising tariffs on European cars. 

By framing your desired outcome within the trajectory of common ground, it becomes an obvious next step, rather than a favor granted to you. 

It is now a win-win for all.