The development and validation of two instruments which measure attitudes and self-efficacy of teacher education students and practicing teachers toward computer use are described. One instrument--Attitudes toward Computer Technologies (ACT)--assesses perceived usefulness of and comfort/anxiety with computer technologies. The second instrument--Self-Efficacy for Computer Technologies (SCT)--assesses perceived self-efficacy for computer technologies (word processing, electronic mail, and CD-ROM databases). These measures were administered to 328 university students in education courses. Principal components analysis of the 19-item ACT found evidence for retaining the concept of the two factors of comfort/anxiety and usefulness. For the 25-item SCT, three empirically identified factors mirrored the concepts of word processing, electronic mail, and CD-ROM data bases. Subscales for both instruments were found to be reliable. Results of regression analyses suggest that actual experience with computer technologies is a strong predictor of attitudes and self-efficacy. These instruments were designed for use with teachers and teacher education students, but could be adapted for other populations. Seven tables present study data. (SLD)