This Research Note is based on a doctoral dissertation to be shorty completed at King’s College, London. It presents first results of one of the largest quantitative analyses of possible causes of Islamist radicalization in Italy, based on a sample of 440 respondents from 15 Italian cities. The study investigates Muslim respondents’ support for violence framed in Islamist religious terms. After defining “Islamist radicalisation”, a large number of models linking support for violence with various predictor parameters were tested. No statistically significant support was found for theories proposing discrimination, economic disparity, outrage at Western foreign policy, oppression of Muslims, traumatic experiences, or any standard sociological variable, including gender and being a convert to Islam, as predictors. Similarly, neither “networks” nor rational choice theory was supported by the data. By contrast, the most significant predictor variables relating to support for violence were taking offense against offenders of Islam and the endorsement of an Islamic, theocratic form of government (ideology). Social difficulties and uncertainty as for the wish to belong to Italian culture (identity crisis) were marginally significant.