PaDiSys is a patient diary system that allows patients and volunteers in clinical trials to use their mobile phones or the web to complete daily diaries in their own language and share outcomes over the cloud. It enables investigators, CROs, and sponsors to access real-time patient data online to monitor compliance, intervene if needed to prevent adverse events, oversee site compliance, and generate compliance reports in order to improve quality and compliance while lowering costs compared to traditional paper-based methods.