Abstract
Affiliate Advertising is a type of advertising in social media, which empower consumers to insert advertising. Thus we can call it Consumer Generated Advertising Media. We conducted Web-based surveys for bloggers including affiliates and for blog readers including ones who have bought from any affiliate. By analyzing the data, we found a paradox that affiliates are more reluctant to reveal profiles of affiliates than others while it is effective to promote purchases. Based on these findings, we discuss the possibility of advertising in social media.