The rule of reciprocation, which says that we should try to repay in kind what another person has provided us, is the most potent weapon of influence we as humans possess. The highly respected archaeologist, Richard Leakey ascribes adhering to the reciprocity system as the essence of what makes us human. He claims that we are human because our ancestors learned to share food and skills in an honoured network of obligation (indebtedness). The sense of future obligation within the rule makes possible the development of various kinds of continuing relationships, transactions, and exchanges that are beneficial to societies. Consequently, all members of societies are trained to abide by the rule or suffer social disapproval.
In negotiation this rule is of great importance. It is at the very centre of the reject-then-retreat and door-in-the-face techniques, both relying heavily on the pressure to reciprocate concessions. The rationale is that by starting out with an extreme request that is highly likely to be rejected, the negotiator can then retreat to a lesser request (that which is actually desired), which is then very likely to be accepted, as it appears to be a concession. Not only does this approach increase the likelihood of a person saying yes to a request, but also it also significantly increases the likelihood that the person will carry out what has been agreed to, and to in future agree to such requests once again.
Sadly we often whittle away the benefits of the reciprocation rule when we have done something for someone else, they thank us, and we respond by saying: "Don't mention it!" What we, however, should say to access the benefit of the rule, is: "I know that if I need your support you will be there for me". This registers a future obligation that is not eroded over time.
Another mistake we often make, relates to the way we respond when someone says no to a request we make. Because we are inclined to see a negative response as a rejection, we are instinctively drawn to then walk away. The most productive response would be, however, to not retreat from the negotiation, but to rather retreat within the negotiation. By not turning our back on the negotiation (retreating from the negotiation), but rather making a concession (retreating within the negotiation), we would not be squandering the law of reciprocation. We would in fact be placing an obligation on the other party to reciprocate our concession.