A Magical Contagion and AIDS Scale was developed to address problems with existing Contagion and AIDS measures. Magical Contagion is an influence that exists after contact is terminated. It is comprised of Permanence, Holographic Effects, Moral Germ Conflation and Backward Action. Data from 280 undergraduates revealed low mean levels of Magical Contagion and AIDS. Contagion effects did not differ on demographic variables. Content validity, criterion-related validity, discriminate validity, and internal consistency were evaluated. Significant correlations were found between the Contagion Scale and Merging/Separation and Homophobia Scales. Negative correlations were found between the Contagion scale and the AIDS knowledge and social desirability scales. Alpha reliabilities were high (a > .93) for the Contagion scale and subscales. Factor analysis suggested the existence of a single factor and mixed support for three factors.