Description Major depression is currently the fourth disorder worldwide in terms of disease burden, and is expected to be the disorder with the highest disease burden in high-income countries by 2030. Estimated costs of depression are annually 177 and 147 million euro per 1 million inhabitants for major and minor depression respectively. Current treatment can reduce the burden of this disease with about one third. The ICT4Depression consortium wants to improve these results and make it easier for patients to access their treatment.The project researchers are developing an ICT-based system for use in primary care, which includes 1) devices which monitor biosignals in a non-intrusive and continuous way, 2) treatments for depression and automatic assessment of the patient using mobile phone and web based communication, 3) computational methods for reasoning about the state of patients, progress of therapies, and the risk of relapse and 4) a flexible system architecture for monitoring and supporting people using continuous observations and feedback via mobile phone and the web. The ICT4Depression system is flexible and can easily be adapted for treatment of other mental diseases. The project will be carried out by an interdisciplinary consortium with 5 (research) organisations and 2 SME companies at the forefront of Artificial and Ambient Intelligence, wireless biosignal sensors, activity monitoring using cell phones, monitoring patient compliance with drug prescriptions, service oriented application for the health care domain, psychology, psychiatry, and internet-based psychological treatment. The project will boost European leadership in ICT-based treatment of mental illness and will provide ample opportunities for commercial exploitation.