Today, very little effort is put toward optimizing the full conversion funnel on e-commerce sites—from landing page through purchase—to maximize sales. In fact, few understand the conversion levers from the top to the bottom of their conversion funnel, and even fewer are equipped with the insights required to press the right ones. The result: An astonishing 97 out of 100 online shoppers leave a site without buying. So what's involved in conversion optimization? Following are the fundamental tenets you need to master.