Hiring an SEO expert or agency can be a tedious experience, especially if you don’t know what questions to ask. Every SEO company has developed unique tactics and techniques that may differentiate them from the field, but if you are not familiar with how to dig out the best information, you may not know. There are certain skills and understanding of the industry that is necessary to run a great SEO campaign, and here are some questions you can ask that will help you find the best fit:
1. Could you briefly explain the PageRank algorithm?

2. What are your thoughts on the direction of Web 2.0 technologies in regards to SEO?

3. What do you think about link buying?

4. Have you ever created an SEO tool from scratch or pieced together others?

5. Explain the various steps you take to optimize a website.

6. From an analytics perspective, what is different between a user from organic search results vs. a type-in user?

7. If you've done 6 months of SEO for a site and yet there haven't been any improvements, how would you go about diagnosing the problem?

8. How do you evaluate whether an SEO campaign is working?

9. Tell me your biggest failure in an SEO project.

10. What do you think is different about working for an SEO agency vs. doing SEO in-house?

These questions may often be about how the answer is given, rather than the answer given. These questions are a great filter for SEO companies who aren’t up to snuff, while the SEO firms that are best for your business will rise to the occasion and shine brightly.