In the b-to-b world, customer feedback such as case studies and testimonials can augment reviews and provide a gentle push for potential buyers who are on the fence about a purchase.

Neal Creighton, CEO and co-founder of RatePoint, a provider of customer feedback and online reputation management services, gives five tips to help you use customer feedback in your own e-mail marketing program:

1) Respect boundaries. Before you do anything, make sure your customers are willing to let you use their words and affiliation. For example, it’s not enough to post a message saying that all responses to a survey are fair game for your marketing department. Take the time to call whoever you intend to feature. This can also be an unobtrusive way to get a salesperson on the phone with that customer.

2) Dedicate space to feedback. Customer feedback—and not just “official” case studies—should be one component of your overall e-mail newsletter. You can create a regular feature that you can use to disseminate one-off kudos, awards or transcripts of call center conversations. Try and mix it up, Creighton said. Feature a case study one week and a quick quote the next. Also, provide a link at the end of the feature so other customers can send you what’s on their minds.

3) Use a Q&A format. A quick message from a customer may not be compelling, but if you go back to that customer and pose a related question, that message becomes a selling tool. Plus, a Q&A is easy to post and provides a quick read, something that subscribers will appreciate. It also turns the spotlight on that particular customer, which can cement the link between your customer and your company.

4) Point to video case studies. We’ve all heard that video doesn’t work well in e-mail, but there’s nothing wrong with sending someone to a video hosted on your Web site. You can transcribe the video and pair that transcription with the link, so even those who don’t want to watch the video can still benefit from its contents.

5) Don’t be afraid of negative feedback. You might think that everything you put out there should be positive, but even a negative question or comment has the ability to turn prospects into customers. “It’s an opportunity to show how you resolve issues with customers. It also shows that you value transparency, which customers like,” Creighton said.