For nearly all of the 273.8 million North American Internet users looking for anything online, the first stop is a search engine. Because search engines are visited so frequently by online users, paid search now accounts for nearly 25 percent of the average online marketing budget. With such a large share of the budget, it is more crucial than ever to make sure your business isn't wasting hundreds or thousands of dollars each month on missed opportunities or inefficiencies. Focusing on the "seven pillars" of paid search marketing will help ensure the highest return on your investment. These seven pillars listed below offer direct marketers a transparent view of each paid search campaign's effectiveness.