The authors conducted 3 studies to develop and investigate the psychometric properties of the American Jewish Identity Scales (AJIS), a brief self-report measure that assesses cultural identification and religious identification. Study 1 assessed the content validity of the item pool using an expert panel. In Study 2, 1,884 Jewish adults completed the initial AJIS and various measures of ethnic identity, collective self-esteem, and religiosity. Using confirmatory factor analyses, the authors selected and cross-validated 33 items that loaded highly and differentially on the 2 theorized latent factors. Study 3 assessed the AJIS's short-term stability and its relation to social desirability. Tests of reliability and construct validity provided initial psychometric support for the measure and confirmed the theorized primary salience of cultural identification. Participants reported significantly more private than public collective self-esteem, and the most Jewish-identified participants reported greater private self-esteem, acculturative stress, and perceived discrimination than did their more assimilated counterparts. (Contains 3 footnotes and 5 tables.)