Belief in conspiracy theories is widespread in society. Whilst belief in conspiracy theories may fulfil several basic needs such as control (., Whitson, et al., 2015), they are potentially dangerous; exposure to conspiracy theories reduces people’s engagement in a variety of domains (., Jolley & Douglas, 2014a,b). Examining tools to address conspiracy theories is therefore timely. Broadly speaking, this novel project will, therefore, build on existing research by exploring the relationship between social norms and conspiracy beliefs and develop interventions that will help combat the effects of conspiracy theories. The project has three phases: (i) a systematic review, (ii) empirical studies understanding the psychological mechanisms underlying social norms and conspiracy beliefs, and (iii) the development of attitudinal and behaviour change interventions (., improving vaccine uptake).