Search engine optimization is increasingly being accepted as a powerful and critical component of the marketing plan. With the costs involved in other forms of online marketing growing significantly, it has become almost a necessity for companies to include SEO in their overall marketing mix.

It's thus no surprise to know that professional SEO today is big business and this industry is growing at a fast pace. There are however many different types of SEO firms out there and finding a reliable service can be a daunting task.

Search engine optimization firms employ varying methods to get high rankings for websites and not all of these techniques are considered ethical. With the increasing number of 'black hat' SEO firms, (companies using unethical and unfair methods and techniques to manipulate search engines), and the thin line between actual 'black hat' and 'white hat' SEO practices, it is crucial to be well informed of the methodology the company plans to use for your website before you decide to hire them.

Here are 8 simple tips to help you in your evaluation and selection of a trustworthy and professional search engine optimization service:

1.Educate yourself with the basics
Make sure to do your homework carefully before you venture out to hire a SEO service. It's imperative you understand in advance exactly what a firm can and will do for you to enable you to evaluate them. There are several resources online dedicated to search engine marketing and search engine optimization and taking the time to understand and learn the basics will go a long way.

2.Fee structures and your budget
There are no standardized fee structures and most companies offer a range of packages instead. A package may in itself contain a variety of services like keyword research, optimization of a certain number of pages, directory submissions etc. Selecting a company should not be only about cost. A firm that charges more may not necessarily be better at SEO and likewise a firm that charges less may not necessarily be providing you the same services. Use prudence while understanding pricing models and the risks behind them. One way to go about deciding what your budget should be is to first identify your website's and business' unique needs, tailor a package to meet these requirements and then compare firms' pricing models to decide a realistic baseline budget.

3.Size and specialty of the firm
Depending on the size of your website and requirements of your company, it might be a good idea to check out whether the firm is adequately staffed and what their customer to SEO team ratio is.

Another important thing is to ensure that the company specializes in all areas of SEO and has a team of professionals experienced and accomplished in each of the areas including design, development and actual coding.

4.Location
The location of the firm largely depends on your comfort level. You may favor a local company or one at least within your country or prefer to outsource completely to another country to benefit from their lower costs. There are also few companies using a blended offshore delivery model with marketing and client services offices in one country and the actual design and development work being done in another. With the combination of lower costs plus client servicing available within reach, this upcoming balanced model may be a good option to consider.

5.Client testimonials and references
References are a great way to start and should be freely available. If they haven't been provided, ask and make sure to use them to find out exactly how credible and trustworthy the company really is based on their past client's experiences.

6.Guarantees
Most firms won't guarantee top position results and shouldn't. It is justifiable for a company to guarantee increasing your traffic or rankings from its current positions; however if any SEO service is guaranteeing you a specific position/ranking in any search engine, make sure you read the fine print of the agreement.

7.Ethics / Spam
Ethics is of paramount importance when it comes to selecting a search engine optimization company. There are a variety of unethical practices a firm can use right from while selling their services to you, to, the actual methods they employ while optimizing your site (keyword stuffing, cloaking, etc to name a few). Make sure to ask as many questions as possible and specifically about the methodology they use. If the firm does not offer you ready explanations of the process they undertake to optimize websites, you probably need to look elsewhere.

8.Reporting and success measurement
Some of the key questions to askHow long will it take to see results? What type of reports will the SEO firm furnish and how often? How will success be measured? Will a maintenance plan be included?

It is largely up to you to define the goal and success level of your SEO campaign. It may be an increase in the traffic to your site, potential leads from a mailing list subscription, or an increase from last years sales. Make it a point to discuss and articulate your goals with the SEO firm and come to an agreement before you hire them. It is however important to set realistic expectations. Unlike PPC and other forms of paid advertising, SEO is a time consuming process, both in terms of implementation as well as results.

To conclude, hiring a SEO services firm can have a significant impact on your company's bottom line, however the decision to partner with a particular SEO firm should only ensue after a careful evaluation of the firm and after you have done the groundwork necessary to help you decide your own goals for the program.