From Google AdSense (please sticky this so that people will stop arguing about it): Hello George, Thanks for your email. According to our policies, publishers are permitted to place three ad units and one link unit on a single page for a total of four content ads. In fact, on any given page, you're welcome to place up to: - three standard ad units - one link unit - two search boxes - four referral units for different products For additional questions, I'd encourage you to visit the AdSense Help Center (http://www.google.com/adsense_help\), our complete resource center for all AdSense topics. Alternatively, feel free to post your question on the forum just for AdSense publishers: the AdSense Help Group (http://groups.google.com/group/adsense-help). I hope you find this information helpful. Sincerely, Lillian The Google AdSense Team
You're always going to get people asking repetitive questions on a forum, especially a forum as busy as this one. I have a job keeping up with the posts since my last visit, let alone from a week ago. For new people (like me), trawling through all the posts can be a nighmare, and even the search facilities don't always throw up the answer you're looking for. It's the patients and helpfulness of other users that makes a good forum.