Battles on Western Front during World War One were the first to see what has become known as Mechanized Warfare. For the first time in our history both armies had an alarming ability to take human life. Both sides quickly developed new tactics to deal with the massive killing power of these weapons including an array of dug out mazes to avoid artillery and shells on the flat expanse. To gain ground soldiers had to leave the safety of the trenches, and face almost certain death in pursuit of a small amount of ground that would likely be retaken days later. This style of battle, known as trench warfare, is well used in discussions about negotiating for good reason. For the inexperienced negotiator well-intentioned attempts to gain ground can quickly turn into disastrous, time consuming and ultimately unsuccessful discussions. In the book Getting to Yes, Bruce Patton, Roger Fisher, and William Ury present an alternative way to obtain the results you want.
There is Never One Reality
First, it is important to not consider a negotiation a factual discussion between perfectly rational individuals, but a conversation between two different people bringing their own subjective interpretations of reality along with personalities, values and emotion to the discussion. Add the normal stress of a disagreement to the conversation and a simple misinterpretation of what is being discussed could easily result in an aggressive and pointless argument. So, how is this avoided?Start by viewing the discussion on two planes. The level of factual argument and the level of human emotion and perception. Take the time to analyze what is happening, reacting slowly to be sure you are responding to the correct level.
Fight the Problem Not the Person
Secondly, consider both parties as a team looking to find a long term solution, not enemies in a battle. Aim to view the situation neutrally, sticking to facts, avoiding personal attacks and insults. Regardless of how frustrated you might be don’t stoop to deeming the other party unreasonable. This will cause distance and could prompt them to lose sight of the real goal. Remember, this isn’t about “winning” or “being right” this is about reaching a productive outcome and no matter how good it feels to express your feelings consider the possible effects on the relationship. 
Focus on Specifics
Thirdly, instead of focusing on your different desired outcomes consider what is in common between both ideas and what underlying desires might be. For example, if you and your spouse were planning a trip and the debate was the mountains versus the sea. Ask specifics about why that destination. Do you want to be by water? What is it you want about that option? What makes you object to the sea? By understanding the other party's driving desires, and identifying your own, a destination that is suitable to both will be much easier to arrive at. With practice and careful thought disputes that once ended in tears or broken deals can be turned into happy parties working towards the same goals.
