Information security issue is the most important one in using Internet and it becomes more crucial while implementing the Internet in banking sectors. This book investigates the current debate regarding the threats and vulnerabilities of the information security of online banking and to study some possible remedial actions to defend the threats and has revealed a lot of risks and threats to the security of online banking information which are increasing day by day. These information security threats have emerged as the main barriers to the adoption of online banking among the customers. It is assumed that, the general perception of the threats of information system will be more practical in future if the success of the information security management within the organizations can be improved. This research presents some real successful fraudulent activities happened in the past and proposes different security measures to protect that. These measures will help customers to develop awareness by education and training and the online service providing banks to develop a safeguard against the frauds by the policy reengineering and using advanced unique technology.