Can I have AdSense and other Ads on my site simultaneously?

I've been reading your book Growing Your Business on Google but you did not answer one question I have. Is it kosher to present Google ads on your site AND present ads from Yahoo or anyone else? Do they insist on exclusivity or can you mix and match?
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Dave's Answer:
You can present ads from both Google (via its AdSense program) and other ad networks on the same Web pages, but there's a very important nuance: you can't have any automatic contextual advertising on the same page.
Let me explain what I mean by contextual ads, however, to clarify this point.
The coolest thing about AdSense is that all you have to do is include their code snippet on your Web page and Google's engine automatically figures out what your page is about and shows the most contextually relevant advertising they can serve up. If you have a dozen pages about a dozen different topics, then you'll find that the ads just magically are always tailored to each page's topic.
Google calls this "content-targeted advertising" and the AdSense terms of service explicitly prohibit you from including any other content-targeted advertising on your pages:
"... You further agree not to display on any Serviced Page any non-Google content-targeted advertisement(s)..."
Fortunately, there are legit and safe ways to sidestep this limitation, though they're not as flexible as AdSense itself. For example, with the new Chitika MiniMall advertising, you can specify a canned set of keywords for the advert to be included as you copy and paste their code onto your page: arguably that's more accurate than letting a program guess what your page is about anyway, but it is acceptable as an additional advert. (See my article Where can I buy a Sony PSP USB cable? for an example of a page with both AdSense and a Chitika advert).
You can also include banner ads (like the BlogAds network) or other advertising. It's all acceptable to the Google team, as long as the other advertising system doesn't automatically scan your page and ascertain the best ads to display on-the-fly.
If you'd like to learn more about AdSense, I suggest you start at my popular tutorial Get Started with Google AdSense.