Many art museum programs aim to facilitate the development of young people's critical-thinking skills, but most are unclear in their definitions of critical thinking and their notions of how it is best facilitated. This article shares a diagnostic tool for identifying instances of critical thinking in art museum programs. Specifically, the authors describe results from an exploratory pilot test of a critical-thinking skills checklist with selected art museum practitioners across the country. Practitioners reflect on the relevance of this checklist to their program goals, its overall usability, and its potential to inform their professional practice. (Contains 4 figures, 1 table, and 8 notes.)