What do you understand from a win-win negotiation concept when you are setting with your customer?

While negotiating contracts every one sets certain parameters this is true for both Customer and company. If you negotiation falls within defined parameters you call it Win Win siatuation. Where company doesn't go an extra mile to win a customer and customer remains in delighted frame of mind.

Normally every one wants to win a negotiation whether it is the buyer or seller. if the buyer win then it mean the seller lost. in this scenario the seller cannot support the buyer on a long run because he has lost the deal ( which means the seller"s  profit is less). the same way if the buyer lost then he will not continue to support the seller. in both cases the business is not healthy. that is exactly the reason if both the parties win then both of them can support each other and continue the business for a very long time. which mean both of them are winning and hence we call it WIN WIN negotiation.

When sitting with the client i always have the goal of finding a mutually acceptable compromise that gives us both as much of we both want as possible.

in the organizations, people's positions are rarely as fundamentally opposed as they may initially appear – the other person may have very different goals from the ones i expect! 

In an ideal situation, i will find that the other person wants what i have to offer, and that i am prepared to give what the other person wants.

If this is not the case and i must give way, then it is fair for me to try to negotiate some form of compensation for doing so, the scale of this compensation will often depend on many factors. Ultimately, both sides should feel comfortable with the final solution if the agreement is to be considered win-win.