Description: Show your counter-party everything you know about your business model, finances, and/or supply chain. Not for everyone.
If you are negotiating for a strategic partnership or a long-term relationship based on trust, then you may agree to reveal sensitive information early. You will decide on what information is necessary to work together, and then reciprocally reveal all pertinent data. This often takes the form of cost models, earning models, supply chain, technical methods and other highly sensitive information.
Note: You should be explicit about what you will disclose in advance, and be very clear about what you expect in return. Full disclosure usually takes place between parties who already have a fairly strong relationship. If you plan on full disclosure being reciprocal, then you have to negotiate that in advance in the clearest possible terms.
Intent: Gain information. Cement a relationship.
Counter: Refuse, and find a way to work with a less trust-based relationship.