When creating a marketing piece, one of the most powerful aspects of effective advertising is offering proof to back up your claims. 
It is important to establish your credibility in order to begin building a potential relationship with your prospect.

The best means is to include a testimonial in your marketing.  Testimonials can be powerful in building credibility for you. 
They can also support the products or services you are marketing.

So, consider including a testimonial in your next marketing piece and see if you notice a difference in the response you receive.

Good luck and happy marketing.

Judith