This paper was produced by the Institute for Strategic Dialogue in advance of the 8th meeting of the Policy Planners Network on Countering Radicalisation and Polarisation (PPN) in Oct 2010. It outlines the role of civil society in counter-radicalisation and de-radicalisation. It sets out the key terms and definitions and the rationale for civil society involvement, provides a number of case studies from European countries, and summarises some of the key challenges and lessons learned for work in this area.