The current economic climate presents many challenges to advertisers. In 2009, advertising spending in the United States dropped 12.3 percent, forcing advertisers to focus on campaigns that prove a quick return on investment. As average time spent online continues to increases, so is the Internet’s contribution to society and the economy. Advertising budgets are being shifted online to reflect the growing importance of the Internet, and much of these budgets are being spent using advertising networks. These networks act as the intermediaries between advertisers and Web publishers and make online advertising accessible and affordable for small and large budgets alike. This paper explores the current state of Internet advertising with a close focus on advertising networks. The goal of this paper is to educate on the basics of online advertising and how to navigate the advertising network industry, so even an advertising novice can utilize their numerous benefits. / text