OpenViBE is a software platform dedicated to designing, testing and using brain-computer interfaces (BCI). The package includes an Acquisition Server application to stream data from various hardware devices, and a Designer tool to create and run real-time signal-processing chains assembled with a graphical design language. OpenViBE package includes several BCI demo applications (based on e.g. P300, SSVEP, Motor Imagery, etc) which are ready for use.