Recently, the number of targeted attacks has been rapidly increasing. Attackers limit their tar- as being malicious and steal data. In addition, large-scale information leakage accidents have occurred due to human errors such as missending of e-mail, and internal fraud. As a measure against missending of e-mail, Fujitsu has developed a tool that warns its users about making a mistake with regards to the recipients or attachments at the time of sending. To deal with tar- geted e-mails, we have extended the tool to alert users to suspicious incoming e-mails based on detection of differences with the header information of e-mails they have received before. Furthermore, we have also developed a technology to detect behavioral characteristics of in - dividuals who are vulnerable to cyber-attacks by examining psychological characteristics and PC operation behavior of people who have experienced virus infection, fraud, or information - users 'security risks, such as user interfaces that warn of e-mail missending and issue alerts for suspicious incoming e-mails, and risk assessment technology based on analysis of psychologi- cal characteristics and PC operation behavior of users.