Knowledge for customer can also be the knowledge sharing among customers. Knowledge sharing can lead to an added value in that it enables customers to know the product/service better with the help of knowledge from other customers. More importantly, the knowledge sharing among customers is perceived as more neutral and trustworthy and thereby helps to reduce customers perceived risk (LopezNicolas & Molina-Castillo, 2008). Despite customers are often dominant in knowledge sharing process, service provider can activate and facilitate knowledge sharing activities by effective customer knowledge management. For example, Amazon.com, as an Internet retailer, successfully creates values for customers through providing order history, reviews and suggestions of other customers (Gibbert et al., 2002). In this way, customers can know more about the products they want to buy and make more satisfactory buying decisions.