Negotiation technique

Most of us assert that negotiation is an art. As per my expertise in negotiating voluminous contracts with various national and international authorities,I opine it is a science because it involves logical power and intuition. There are two types of negotiation predominantly in vogue,one is soft another is hard. In hard negotiation, people and substance both become important whereas in soft negotiation, people matter more. Here both the parties are watchful not to spoill relationship and then negotiate to arrve at the conclusion. In hard negotiation, matter is simply opposite.To overcome this situation,I strongly suggest to
accept the method of "Principled Negotiation". In today's world of fierce competition, this method is the correct approach to offset the competition to the extent possible so as to clinch the deal.I profusely apply this technique ,but then what is yours?