Clinical research is a dynamic, complex and constantly evolving endeavor/enterprise that requires extensive resources to develop and maintain a clinical information system meeting clinical investigator's diverse needs. CiSTAR is the first attempt of an international collaborative development project for a clinical research information system at NIH. The system merges two existing clinical information management systems into a re-designed modular system to support various types of clinical trials and research. It is recognized that every clinical study design is unique; therefore, to encourage biomedical innovations the information system must be flexible to adopt to various types of data collection and management needs