This is a big question, but I'm hoping for a small answer: what's your #1 favorite recommended technique for having a successful online advertisement? You're right, this is a pretty darn big issue, but it turns out that there is one key to a really successful advertising campaign online, one key idea that a surprising number of companies fail to do. The key? Create a custom landing page for each of your creatives Whether it's a text-only pay-per-click AdWords advertisement or a expensive Flash-based graphical advertising campaign, your ad promises the viewer something, be it a product, service, discount, or even just more information. The landing page then has to deliver on that promise. That lack of a custom landing page, that lack of follow-through, really cripples this campaign and while I might even have considered purchasing the gadget - whatever it is - I'm sure as heck not going to dig through the entire product catalog to find the device they paid so much money to advertise on the NY Times. Can you see the disconnect here and why HP lost a potential sale, even having produced some interesting creative and positioned it on the New York Times home page? If the landing page would have been more information about the product, and even perhaps a special discount offer for Times readers, they might have closed the sale. As it is, however, they just left me shaking my head, wondering why they hadn't done better.