Electronic commerce, that allows business to be performed over the Internet, has been a major trend in this century. Many businesses arc moving on-line. However, there are neither guidelines nor theories to show how electronic store features affect consumer purchases. This paper uses a consumer-oriented perspective to derive functional requirements far e-store design. These needs are grouped into three categories: motivation, hygiene, and media richness. An empirical study was conducted on three on-line bookstores to evaluate the relative importance of these factors. The results show that the quality of e-store design has an effect on the consumer purchase decision. Consumers are more likely to shop at well-designed websites. Among the on-line functions, support of transaction and post-sales services play key roles. Hygiene factors are critical when consumers decide whether to shop electronically, while motivational factors play a key role inhere consumers choose among different electronic stores. Media richness factors are, in general, least important. The implication of the findings is that providing good transactional support and post-sales services to the customer is the key. (C) 2002 Elsevier Science B.V. All rights reserved.