Google AdWords has a sort of measuring stick they use called "quality score." The quality score is applied to your campaign, and to your ad group within a campaign, and to your individual keywords within the campaign.

Your quality score is important because the better your quality score, the less you will pay for whenever someone clicks on one of your ads. And conversely, with a low quality score your cost per click goes up significantly.

Here’s what Google says about the quality score:

"The AdWords system calculates a 'Quality Score' for each of your keywords. It looks at a variety of factors to measure how relevant your keyword is to your ad text and to a user's search query. A keyword's Quality Score updates frequently and is closely related to its performance. In general, a high Quality Score means that your keyword will trigger ads in a higher position and at a lower cost-per-click (CPC)."

So we can see that your quality score is important because it affects how much you will pay for each click. This is vital because, especially with the amount of companies using Google AdWords today and competing for your keywords, if you’re not careful your costs can get out of hand and your campaign will not be viable. And when I say not viable I mean that you can end up paying too much for each lead or sale that you get.

"In general, the higher your Quality Score, the lower your costs and the better your ad position."

"Quality Score helps ensure that only the most relevant ads appear to users on Google and the Google Network. The AdWords system works best for everybody -- advertisers, users, publishers, and Google too -- when the ads we display match our users' needs as closely as possible. Relevant ads tend to earn more clicks, appear in a higher position, and bring you the most success."

It’s a little bit of work to sort through what they are saying and what you actually have to do in order to improve your quality score. So here it is simplified.

Relevancy: Your keyword, your text ad, and the content you have on your landing page have to all be the same topic. If for instance you have a set of keywords that are all very similar, and your text ad is about that same topic, and then the content of your landing page is all about that same topic, that’s good. You will get a good quality score. This also means that you should eliminate from your ad group any keywords that are only slightly related to what is on your landing page, as including them will lower your quality score.

Clickthrough Rates (CTR): In general, the higher your overall clickthrough rate is for a given ad group or campaign, the higher the ad group’s or campaign’s quality score will be.

There are several important implications for this. One is that between the search network and content network (which Google is now calling the "display network") the search network always gets higher clickthrough rates, by far, than the display network. So it is best to set up one campaign that only goes to the search network, and another that goes only to the display network. That way, the quality score of your search network campaign will be much higher than if you just had both networks together in one campaign.

Another implication is that you should remove keywords from your campaign that have really low clickthrough rates, because including those in the campaign will lower its quality score. I called Google recently and found out from them that if you have a keyword which is getting impressions but has NO clickthroughs, that will not affect your quality score adversely. But as soon as that keyword gets one clickthrough, if the percentage is low, now it will affect your quality score adversely.

Search and Display Network: I recently read a book called the "AdWords Manifesto," where the author said that for your search campaign, you should choose tightly focused keywords that are only on one topic, so that it has good relevancy. Then for your display network campaign, you can throw in related keywords and make it more broad. I actually called Google about some of the things in this book to ask if they were true. The Google rep said that this is not true, and the opposite is true, i.e. you can have a broader selection of keywords on the search network and a more focused group on the display network.

Landing Page is Not the Home Page: Many people put up a Google AdWords campaign and have their text ad set up so that when someone clicks on it, the visitor goes to the home page of the advertiser’s web site. This is not ideal and can hurt your quality score, because chances are your home page does not specifically talk about the specific product or service you are advertising in detail. This is especially true if your company has multiple products or services. So if the visitor lands on your home page and it doesn’t even mention the product being advertised, or just briefly mentions it, that hurts your quality score. Better to create a customized page for your Google visitor to land on.

Keywords in Text Ad: Including your keywords from your campaign in your text ad improves your quality score.

Keywords in Headlines: If you include your keywords from your campaign in the H1 and H2 tags, which are used to define your headlines in an HTML page, that helps your quality score.

Good luck with your Google AdWords campaigns.