Belief in conspiracy theories is on the rise and has been associated with a variety of worrisome attitudes and behaviors, from a diffuse distrust toward institutions to the justification of antisocial behavior and, in some extreme cases, to active involvement in terrorist organizations. Many countries have deployed important means to fight against radicalization, including TV spots and phone centers for families to inform about suspect behaviors among their relatives or friends, which often involve advocacy of conspiracy theories. The aim of the present project is to design and assess responses to the issue raised by conspiracy theories beliefs. This will be achieved by identifying relevant cognitive and personal factors that may favor conspiracy theories endorsement; evaluating already existing attempts to reduce conspiracist ideation to set a benchmark; and developing evidence-based intervention programs.