There are an astonishing number of tools one can use to influence the decision- making process of individuals. The seven levers of influence refer to specific overarching methods, though within each of the levers there are a plethora of ways to engage that specific principle. These “levers” reveal the essence of influence and how and why people respond to them.

For example, Cialdini describes the lever of “reciprocation”: extending generosity to a potential customer in hopes the customer with respond in an archetypical manner by extending generosity in return. When a customer samples a tiny cup of food in a market, the owner hopes the customer will respond by making a large purchase. Reciprocation, however, can take on subtle aspects as well. The author writes of the rejection-then-retreat gambit: A compliance professional makes a request, knowing it will likely be declined; after the customer declines, the professional makes a second request that is less burdensome. Feeling that the professional has given them something—a concession—the customer complies with the second offer.

Perhaps Cialdini’s greater achievement is to have discovered, analyzed, and listed for the first time those processes that human beings have used and adapted since before recorded history.