The TAO framework is an open-source project which provides a very general and open architecture for computer-assisted test development and delivery. As upcoming evaluation needs will imply the collaboration among a large number of stakeholders situated at different institutional levels and with very different needs for assessment tools, the TAO framework has the ambition to provide a modular and versatile framework for collaborative distributed test development and delivery with the potential to be extended and adapted to virtually every evaluation purpose that could be handled by the means of computer-based assessment.