The art of negotiation is the ability to combine scientific analysis of a strategic situation with the scientific knowledge of bargaining theory and the psychology of intuition and experience to a negotiating strategy in order to largely attain the aspirations on the result of the negotiations.
There is a vast flood of books with tips and tricks of negotiations. They all share the belief that with the "seven", "101" or what ever best tricks, one will become a successful negotiator. Of course, it is helpful to read such literature in any case, because any discussion of many ideas and examples increases the experience and knowledge in this area.
In principle such negotiators significantly are superior to people who are convinced that their negotiating skills were already acquired in the sandbox, but the complexity of most negotiation problems is so that it is out of their depth.
The first known book on the art of negotiations was written in the 17th Century by the French diplomat de Callières (1645-1717). In his 1716 book "De la manière de négocier avec les Souverains" he described a code of conduct for negotiators, which is still an essential part of the whole literature on this topic.
Current scientific evidence, particularly from research on game theory and on experimental economics, have not been sufficiently taken into account. In many cases in literature there are still recommendations, which contradict scientific evidence.