This article presents the authors' response on the two commentators' (Fred Davidson and Charles Alderson) reviews of the 2009 Special Issue of "Language Assessment Quarterly" on "Cognitive Diagnosis and Q-matrices in Language Assessment." The Special Issue represents several years of research work on cognitive diagnosis approaches (CDA) carried out by the authors of the four main articles in the issue. The reviewers' comments assure the authors that they have accomplished their initial goals of informing and updating language testers of groundbreaking work on CDA and recent developments in CDA applications to language assessment. Their goals in this article are two-fold: (1) to respond as co-editors to the general comments made by the two commentators regarding the entire issue; and (2) to respond, as co-authors, of the first (Lee & Sawaki, 2009a) and fourth (Lee & Sawaki, 2009b) articles in the issue, to the specific concerns raised by Charles Alderson regarding these two articles.