The author offers some thoughts on commentator's reactions to the substance of the measures, particularly those about measuring teacher learning and change, based on the major uses of the measures, and because this is a significant challenge facing test development as an enterprise. If teacher learning results in more integrated knowledge or different forms of knowledge at different points along the growth trajectory, this must be understood and captured in any assessments. Besides mundane issues involving equating of tests, content comparability across parallel instruments, etc., Kulikowich's comments suggest that there remains important conceptual and statistical work to be done before currently available measurement instruments capture growth in knowledge. (Contains 1 footnote.)