(This post is part of a series created to help you help your advertising agency create effective communications for your business.)

So you’ve finally crafted your proposition, and it’s a good one.

You’re now on the last leg of finishing your agency brief. This part is easy. It’s basically giving your audience (or target market, if you want to be technical about it) very good reasons to believe you.

This comes in two parts: the reasons to believe (RTB) section, and the substantiation.

Often a cause of confusion among advertisers (and even their agencies) the  difference between the RTB and the substantiation is very simple: one is logical, while the other is often technical. If your proposition is a case you are building for your product or service, the RTB are the arguments that support your case, while the substantiation is the different form of proof why your arguments are valid.

Say, for example, you want to say that your product is the best defense against turning into a zombie.

For your RTB, you may want to include why it’s the best (i.e. unlike other products that still cause loss of brain cells, the number of people who  have managed to avoid being turned into zombies by using your product versus that of other products), that it helps prevent brains from being turned into mush, and the fact that it is both zombie and zombie-master repellent.

For your substantiation you will want to include the ingredients, the endorsements of the anti-zombie invasion researchers as well as the clinical tests that have proven it so.

Yes, it’s that easy.

If you’ve been following this series so far, by this point you will have completed your agency brief. Now all you need to do is send it to your agency. Don’t have one yet? Drop us a line, and we’ll see how we can help you with that.