This Prolinnova Working Paper highlights practices in and perceptions on the use of a Participatory Innovation Development (PID) approach and discusses some issues regarding integration of this approach into the existing agricultural extension system in Tigray Region of Ethiopia. It is based on a case study made in late 2010 to track the process of PID institutionalisation in the Tahtay Maychew District Office of Agriculture. The paper, to be found here, describes procedures and processes taken towards institutionalising PID and indicates the factors that trigger or hinder the change process