In this article, the author echoes his co-author's and colleague's pleasure (Hill, this issue) at the thoughtfulness and far-ranging nature of the comments to their initial attempts at test validation for the mathematical knowledge for teaching (MKT) measures using the validity argument approach. Because of the large number of commentaries they have received, it is impossible to address fully all the points and observations raised in the commentaries. Moreover, the necessity to provide a timely response precludes giving the sort of detailed response that each commentator's unique insights warrant. Rather the author selectively uses the points raised to help illustrate important points not addressed in their original papers, points that were unclear, or points brought into sharper focus due to the insightful nature of the commentaries. The key points are as follows: (1) Their belief in the utility of the validity argument approach, their agreement with Kane with respect to the importance of the distinction between the formative and summative stage of the validity, and the importance of a clearly specified interpretive argument; (2) The question of the degree to which generalizations can be made with respect to the form, content, and structure of the interpretive arguments and the degree to which interpretive arguments are unique; (3) The ongoing nature of validity research and the incompleteness of the research reported here; and (4) Implications for future work on test validation, particularly what future papers might look like and how should the results of that research be organized and reported.