Perceived security is defined as the level of security that users feel while they are shopping on e-commerce sites. The aims of this study were to determine items that positively influence this feeling of security by users during shopping, and to develop guidelines for perceived security in e-commerce. An experiment allowed users with different security assurances to shop on simulated e-commerce sites. The participants were divided into three groups, shopping for cheap, mid-range, and expensive products, respectively. Following the shopping environment, the virtual shopping security questionnaire (VSSQ), consisting of fourteen perceived security items, was presented to the users. The VSSQ was presented to the participants to validate these perceived security items. The VSSQ had a Cronbach's alpha internal reliability value of 0.70. With the exception of two items, there were no significant differences in item ratings between the groups of different shopping item values. A factor analysis procedure determined two main factors concerning perceived security in e-commerce. The perceived operational factor includes: the site's blocking of unauthorized access; emphasis on login name and password authentication; funding and budget spent on security; monitoring of user compliance with security procedures; integration of state-of-the-art systems; distribution of security items within the site; website's encryption strategy; and consolidation with network security vendors. The perceived policy-related factor includes: the website's emphasis on network security; top management commitment; effort to make users aware of security procedures; the website's keeping up-to-date with product standards; the website's emphasis on security in. le transfers; and issues concerning the web browser.