I'm not here to make the case for content marketing.

The fact is, it's an open and shut case. Audiences have come to expect, want and even demand compelling, intelligent and entertaining content from brands.

All of the statistics out there point to the power of content marketing in engaging new clients, maintaining old clients, deepening brand loyalty and, most importantly, enhancing the bottom line.

The only real question is whether your content marketing program should be handled internally or externally. The fact is, there is no single answer to that question.

Many big brands have built large in-house newsrooms or have even set up their own publishing houses. Some of the brands doing this most effectively are Red Bull, Coke, IBM, Cisco, Nissan and GE.

Similarly, many smaller, entrepreneurial companies have taken the content marketing plunge and have done it very successfully. These companies made the investment in time, personnel and budget to have an in-house team with great written, visual and strategic abilities.

For many smaller companies, though, handling their own content maketing programs doesn't make sense. When the content a brand creates is mediocre or worse, it makes a negative statement about such brand. Creating compelling content requires a specific skill set and most small companies don't have that internal capacity.

Using an outside agency to handle content marketing is often the best choice for small, entrepreneurial companies. In many cases, smaller companies are laser-focused on their business and have neither the expertise or interest in creating their own content.

While there are a number of such agencies doing spectacular work, there are many more out there whose work is, at best, sub-par. Anyone with a degree in English (or any other major for that matter) can hang a shingled and call him/herself a content marketer.

To find a legitimate content marketing agency that will help to take your business to the next level (and beyond) I suggest you do the following five things:

  • Google "Best Content Marketing Agencies": This may sound like a no-brainer, but this search will provide you with a number of suggestions from reputable publications. It will also steer you to various content marketing awards. In fact, when I recently performed this search, the No. 1 result was an announcement of the finalists for the Content Marketing Institute's Content Agency of the Year Award. Finally, when the results show specific companies, you can be assured of at least one thing; if the company shows up on page one of Google results for this search, it means the company has a thorough knowledge of search engine optimization.
  • Take a close look at their case studies and ask for referrals: When interviewing a content marketing agency, make sure they have a track record. It is important to read between the lines of a case study. Does it speak in generalities or does it provide meaningful metrics. Does it provide the budget for the project and the specific ROI for the content marketing program. In terms of testimonials and recommendations, go beyond what they provide in their marketing materials. Make a point of speaking to the clients directly. Ask them: Was the agency easy to work with? Were they responsive? Did they deliver in a timely manner? Were they flexible?
  • What kind of content marketing do they do for themselves? In other words, do they just talk the talk or do they walk the walk. Do they have a blog? Do they produce engaging and informative videos? How well do they utilize social media to promote themselves?Many of the best content marketers are also known thought leaders in the field. Look to see if the agency's leadership are actively contributing articles, speaking at industry events and engaging large audiences on social media. While Klout has its flaws, a person's Klout score does provide a clue to their level of influence.
  • How strategic are they? Content marketing goes well beyond just creating compelling content. Content marketing is a means of strengthening impressions about a brand and driving desired customer behaviors. Simply writing articles or creating videos with no specific business goals behind them is useless. When interviewing an agency, make sure to grill them about how they approach the strategic aspects of their work. Going back to my point on case studies, there should be significant discussion of the thought behind the content marketing program and how each element of the program was designed to help achieve those business goals.
  • How do they measure success? A well-designed content marketing program needs to be measurable. There are all kinds of tools out there (well beyond Google Analytics) that can tell you precisely how effective your content is at driving your business goals. When an agency prefers to talk in generalities sand buzz words than in hard numbers, it's time to politely get up,say "goodbye" and look elsewhere.