The objective was to develop a brief questionnaire to assess short-term functioning decrements in adolescents with acute migraine. One hundred twenty-three potential items were generated by literature review and by interviewing adolescent migraineurs and migraine specialists. To reduce the items, 127 adolescents were asked to identify which items affected their daily functioning in the 24 hours following onset of a migraine, and to rate them on a 5-point scale from “not very important” to “extremely important.” Reduction to an 18-item questionnaire was performed by evaluating subject-perceived importance (number of times an item was chosen times mean importance score) in combination with principal components factor analysis. Five domains were identified: (1) activities, (2) social functioning, (3) cognitive functioning, (4) migraine headache symptoms, and (5) emotional functioning. Questions regarding school loss and school performance during a migraine were added to the final questionnaire as a separate outcome measure. The correlation between the five domains as measured by the Spearman correlation coefficient ranged from 0.17 to 0.49 suggesting some, but minimal, overlap. Cronbach alpha for individual domains ranged from .50 to .84. The questionnaire was pilot-tested in 12 adolescent migraineurs to determine ease of administration and comprehension and revised to improve clarity.