Animosity towards the United States. Support for radical Islam. Violence as political activism. Scope and methodology. Report structure -- The theoretical underpinnings of strategic influence. The psychological objectives of persuasion. The necessary sequence of events and timing. Key judgements -- Theory into practice : what influence can hope to achieve. Methods of influence -- Performance measures. The dangers of failure. Key judgements -- Potential audiences in Muslim communities. Yemen. Germany. Indonesia. Key judgements -- Implications for the struggle against terrorism. Guiding principles. Translating the principles to policy. Conclusion -- New challenges ahead.