Imagine this. Yesterday you called at two stores to enquire about a new mobile phone. At one store the assistant was courteous, efficient, knowledgeable, but aloof. At the next store, the assistant was equally professional, but you develop a rapport. Let's say the deals are the same.

You'd buy from the second store, right? If the first store offered a slightly better deal, would you change? How different would the deal have to be to persuade you to go back to the aloof assistant?

We are more easily persuaded by people we like. Liking is one of Robert Cialidini's six principles of influence. Cialdini is Emeritus Professor of Psychology and Marketing at the University of Arizona. He's done the field work, by working undercover with people who use those techniques to manipulate us into saying yes.

So how can you use the liking principle in a non-manipulative way?

Let's say you want your readers to read all of your report or agree to your recommendations. Just write in a friendly conversational style. Eliminate all the bureaucratic stuff. Show that you are interested in your reader's perspective by answering their questions before they even raise them.

How can the liking principle help in sales?

It's the same idea. Write your proposals of a conversational tone. Show a real interest in your customers' needs.

Salespeople are often taught that they must try to get the customer to like them. Cialdini says it's the the wrong approach. Instead, make an effort to like your customer.