This bias describes the urge we have to reciprocate the actions others have done towards us, returning the favour where we can. However the reverse is also true – unfriendly or negative actions will engender more of the same.

Using reciprocity in marketing is about leveraging the fact that we respond in kind to even the smallest act of generosity or altruism.

A lovely, simple example of this can be found in a story from entrepreneur and writer and blogger Sam Parr. Parr had gone to buy a motorbike off Craigslist, and after previous experiences felt awkward about haggling the price down. However, being a smart young man he’d read about a famous Coca-Cola experiment conducted by professor Dennis Regan, in which participants were more likely to buy from someone after receiving a bottle of Coke, even if they didn’t actually like them. Armed with this knowledge, Parr bought a couple of bottles of the stuff before arriving at the sellers house. After some chit chat and a test ride, the time came to agree a price. Parr went in at $1600 which the seller felt was too low, sticking to the $2200 he’d originally hoped for. Parr then pulled out $1800 in cash, and reminded the seller that most buyers on Craigslist ‘flake anyway’, and was surprised by the response – “Well, since you brought me something to drink, I guess I can do $1,800.”

Parr said: “Sellers are ready to go to war. They anticipate lowballers, tire-kickers, and flakes…so when a prospective buyer does something nice for you, even if it’s as small as a smile and give you a Coke, you’re completely caught off guard with the kindness.”

Moving from free Coke to free content, Hubspot is brilliant at offering a ton of lovely, valuable stuff to help you along your marketing journey. From whitepapers to training, they are essentially giving away value for free, stuff that is genuinely useful to their audience of marketers.

When content enables readers to yield results, they’ll feel grateful, and are more likely to reciprocate by providing their email addresses for future updates. They become valuable leads or better yet, they feel indebted to you and go on to buy.

• Help first, sell later – think about small, scalable ways you can provide service or utility to your customers, before you think about what you can sell them.
• Tat won’t cut it – giveaway stuff of real value, whether it is content or physical items that enhance your customer experience.
• Personalisation – something as simple as a handwritten note can increase engagement response rates by three times. Can’t manage it at scale? Use a service like Inkpact.
• Be nice – borrow from car salesmen, they know it’s harder to walk away from someone friendly and will go out of their way to make you feel welcome, with coffees and chit chat.

For a short time only we are also offering a free one-hour training workshop to inspire, surprise and expand the minds of your brand and marketing teams on some of marketing’s hottest topics.