The aim of Cloudi/o is to provide a generic solution for secure, efficient, cloud-based data management in clinical research. Cloudi/o consists of seven components arranged in the four layers of data management, security, interoperability, and communication. The Cloudi/o framework was developed based on state-of-the-art technologies and supports the workflow of clinical trials through web-based and dynamic IT services. Thanks to tablet use, these services can make work processes more flexible, more location-independent, and less expensive. The cloud approach requires appropriate security measures in order to counteract the threats to data security and data protection.