Case studies -- often called customer success stories -- are a valuable marketing tool. Sure, your prospects will read your brochures and websites. But, they'll take what they hear from you with a grain of salt. Customer success stories tell the story of your company through your client's eyes, and as a result they carry a great deal of weight with your prospects.

Writing a marketing case study has seven basic steps:

1. Client selection. First, pick the client you would like to see featured in your customer success story. Their overall experience with your company should be positive, and they should have measurable results to show your company has created a return on investment for them. Once you've selected your client, ask for their permission to tell their success story and explain what's in it for them -- for example, increased brand awareness and possible media attention.
2. Writer selection. You have two options for writing your case study: outsource the project or create it in-house. Many companies choose to use freelance copywriters because it's often easier for clients to share their opinions with someone outside your company.
3. Interview process. Before interviewing your client, the writer should gather all the information they can internally. It pays to be prepared. During the interview, ask open-ended questions about the challenges the company faced, why they chose you as their solution, and what type of results your solution has generated.
4. Writing. The typical format for case studies is background, challenge, implementation, and results. Essentially, you are presenting the customer's story from beginning to end. But, feel free to use creative headings or even change up the format if it makes sense. Customer stories can tend to be formulaic, and a little variety shakes things up. Be sure to include as many hard facts and return on investment numbers in the case study as possible -- facts and figures are the best way to demonstrate results.
5. Review and approval. Carefully review the final customer story, and have your client do the same. Keep in mind that several people at your customer's organization may have to sign off on the case study project -- including marketing, public relations, and the legal department. This can sometimes take time, so be patient and follow up when necessary.
6. Design. Use a graphic designer from your in-house graphics department or a freelance designer to lay out the case study with plenty of graphics and white space. Pull quotes, sidebars, charts, graphs, and photos make interesting additions to your customer story's layout. If you don't know any freelance graphic designers, your freelance writer can likely recommend one.
7. Distribution. Once your case study is finished, get the word out. Send it to bloggers in your industry, trade journals, the local media, your email lists, and include it in your newsletter. And, make sure to print up some copies for your sales force. They'll find it's a powerful tool to use throughout the sales process.