A valid, reliable, and age-appropriate instrument to measure adolescent responses to menarche was constructed. The Adolescent Menstrual Attitude Questionnaire is a 5-point Likert scale (with six sub-scales) with versions for pre- and postmenarcheal girls. Scale development included (a) content validation, (b) testing (with 860 premenarcheal and 1,013 postmenarcheal girls), (c) discriminant analysis (to identify items unique to the pre- and postmenarcheal experience, (d) construct validity using principal component factor analysis, and (e) reliability analysis. Development of the scale revealed that on some dimensions, the attitudes of premenarcheal girls were qualitatively different from those of postmenarcheal girls. Thus, the final versions of the Adolescent Menstrual Attitude Questionnaire consist of 58 items each, with 43 common items, 4 common items that load on different subscales, and 11 unique items. Reliabilities (r) are .91 and .90 for the pre- and postmenarcheal versions, respectively.