Over the past two decades, the scenario in the computing world has evolved from client-server to distributed systems and then to central virtualization called as cloud computing. Computing world is moving towards Cloud Computing and it remains as buzzword of the current era. Earlier, users had complete control over their processes and data stored in personal computer where as in cloud, cloud vendor provides services and data storage in remote location over which the client has no control or information. As application and data processing takes place in public domain outside the designated firewall, several security concerns and issues arise. The main objective of the paper is to provide an overall security perspective in cloud Computing and highlight the security concerns and other issues. The paper also highlights few technical security issues in cloud computing. © 2011 Springer-Verlag.