If you are looking to hire the services of a search engine optimization freelancer or company, you are going to be spoilt for choice. For you to be happy with and decide who to entrust your funds and website with, you are of course entitled to ask as many questions that you can think of.

Legitimate SEO people will be more than happy to answer your questions to help promote their services, so don’t be afraid to ask any questions that you have. With the search engine optimization industry being in it’s relative infancy though, there are many people who are yet to truly understand the process and what to expect. With this in mind, here are a few questions that you could ask us, or anybody offering SEO services.

Overture, formerly GoTo until October 2001, -- and now known as Yahoo Search Marketing -- is a paid placement search engine. This means that you can pay to get top placement for the search terms you want.

Yahoo Search Marketing is also a paid listings distribution network that provides its listings to many other search engines. Yahoo itself estimates that more than 90 percent of users see its links at their partner search engines instead of at the Overture site.

Google has developed their own pay-per-click program called Google Ad Words. The Ad Words program allows listings to appear in boxes that run along the right-hand side of Google's results page. These are sold on a self-serve basis, which means you can get started almost immediately, as long as you have a credit card.

1. How long have you been providing search engine optimization services?
2. Can you name some of the changes to my website that you may make?
3. Can you provide examples of your previous clients and the results you achieved?
4. What was the client’s ROI?
5. What type of volume increase in traffic is reasonable to expect?
6. How long until I start to see results?
7. What would you expect from OUR end to aid your work?
8. What were some of your top search ranking achievements?
9. Name the three most important elements in the head section of an HTML document that are employed by search engines.
10. How do search engines treat content inside an IFrame?
11. What resource and query can you use to determine which pages link to any page on SEOmoz.org and contain the words "monkey" and "turnip"?
12. What action does Google threaten against websites that sell links without the use of "nofollow"?
13. What is the difference between local link popularity and global link popularity?
15. Why is Alexa an inaccurate way to estimate the traffic to a given website?
16. Name four types of queries for which Google provides "instant answers" or "onebox results" ahead of the standard web results.
17. Describe why a flat site architecture is typically more advantageous for search engine rankings than a deep site architecture.
18. What kind of tracking and measurement do you have in place?
19. What kind of reporting do you do?
20. Do you use any methods that might be considered black hat SEO?