Know how to make a case for a particular position and how to explain this.
The point to be made should be clear and specific if possible. It may be better to make complex points by identifying a series of the component parts of the main point and making a case for each. Consider the evidence or support or reasons for the point that is to be made. Prioritise these within the context of the negotiation. When considering supportive evidence, look for things that are affected by changes to the point being made.
The knowledge named 'Construct an argument' is considered to be quite critical.
In addition, the knowledge is thought to be rather complex and difficult to learn, it is mostly learned from experience, and is specialised knowledge.
Opinion is that it is slightly justifiable knowledge.