The purpose of this article was to develop and evaluate evidence for reliability and validity of a multifactor measure of evasive attitudes of sexual orientation across two studies. The Evasive Attitudes of Sexual Orientation Scale (EASOS) was inspired by Neville, Lilly, Duran, Lee, and Browne’s (2000) Colorblind Racial Attitudes Scale and existing literature on contemporary homonegativism. In Study 1, data from 221 heterosexual participants were included in an exploratory factor analysis (EFA) and resulted in a 3-factor solution: Institutional Heterosexism, Aversive Heterosexism, and Heterosexual Privilege, with 1 global factor of Evasive Attitudes of Sexual Orientation. Correlational analyses with the present sample revealed evidence of convergent validity and a lack of response bias. The sample for Study 2 included 270 heterosexual participants. EFA results from Study 2 confirmed the factor structure found in Study 1. Hierarchical regression was used to assess incremental validity of scores in the newly developed measure. Results indicated that the EASOS explained participants’ degree of lesbian, gay, bisexual, transgender persons (LGBT) allyship better than measures of homonegativity and modern heterosexism could alone. The present findings offer initial evidence for the use of the EASOS and may be valuable for future research on contemporary homonegativism.