Many people don't realise that affiliate software has more uses than just "simple" affiliate management. It can be used to track activity (including conversions and ROI) of campaigns running on AdWords, Overture, or anywhere else.

First question is - why should you do it?

Most of the advertising systems do have some kind of sale conversion tracking.

This is true, but there are some benefits when you use your affiliate system to do the work:

You can compare the results of different campaigns

Affiliate software (if it's good one) will allow you to easily view reports of clicks, sales and conversions for given campaign. You can easily find out what pays of and what not.

Moreover, by comparing conversion ratio of different campaigns you can identify the weak points and try to improve them.

What if you'll find out that your Overture campaign converts much less visitors into buyers than AdWords?

If you know this, you can try to improve it. And when you make a change, the affiliate system will tell you again if your sale conversion increased or not, and how it compares to others.

No need to include multiple sale tracking codes

It is simply less work. When you have affiliate software installed, it already contains the sale-tracking snippet.

So you don't need to edit your pages and place the sale conversion codes for every new advertising system you plan to use, you'll simply use the affiliate's system build-in sale tracking capability.

It allows you to track also systems that don't implicitly offer sale conversion tracking

Google AdWords and Overture do have sale conversion tracking, but what if you buy campaign somewhere else? Or banner placement, sponsored listing, etc.?

You can even track free listing or text link included in some web directory or your friend's web page.

My company uses multiple marketing channels, for example we pay for sponsored listing on HotScripts. If we don't track it with affiliate system, we would have no idea how many visitors HotScripts sends to our page, and how many of them actually made a purchase.

Now, if I persuaded you that tracking ROI and conversions using affiliate system is a good idea, let's move to the next step - how to set it up.

It depends on the affiliate software you use, but most of them will have this functionality.

First of all, what can be tracked?

pay-per-click campaigns on Google AdWords, Yahoo Marketing and similar your own link exchanges with another website your paid advertisements on another web sites etc.

The principle is simple - you should create a special "virtual" affiliate for every system or campaign you want to track. Then use its affiliate link instead of your website URL in the campaign destination. That's all. Now the traffic and conversions coming from Google AdWords will be tracked. Because you used affiliate link as a destination URL, the traffic from Google AdWords will be sent to this link.

Google acts as your affiliate, but because it is virtual account for your own use, you don't need to pay it any commission from affiliate system.

CONCLUSION

Affiliate software can simplify your life by tracking your ROI and conversions from multiple different external systems and/or campaigns (like AdWords, Overture, HotScripts, etc.), and providing reports and comparison of the results.