The content validation method was used to develop a scale for measuring attitudes toward and knowledge about the Acquired Immune Deficiency Syndrome (AIDS) for college students. The developed instrument, the Attitudes toward AIDS Scale (ATAS) consisted of a knowledge scale and an attitudes scale, each with 25 items chosen by a pool of AIDS educators and researchers. Subjects for an internal consistency reliability study were 320 college students (166 undergraduate students and 154 graduate students) in a large university on the East Coast. Fifty-two of the undergraduates participated in a test-retest reliability study. Results indicate that both scales of the ATAS have adequate internal consistency and test-retest reliability. The ATAS provides an adequate instrument for conducting AIDS research and evaluating the effectiveness of AIDS education and prevention effects. Three tables present study findings. There is a five-item list of references. An appendix lists the 50 item statements that comprise the ATAS. (SLD)