The α2β1 integrin (VLA-2), one of the first integrins to be identified and characterized, is a collagen receptor, although it can function as a dual collagen/laminin receptor on some cell types. ¹ Numerous studies have implicated this integrin in a range of biological and pathobiological functions. ^2,3 A more rigorous analysis of α2β1 function has been hindered, however, by the lack of an α2-deficient mouse. Given that mice with null mutations in other well-studied integrins that are related to α2β1 in either their expression pattern or function [α1 (α1β1);α3 (α3β1); and α6 (α6β1; α6β4)] have been available for several years and have provided considerable insight into the function of these integrins, this situation was rather surprising. Fortunately, this issue has been remedied. In this issue of The American Journal of Pathology, Zutter and colleagues report the generation and initial characterization of an α2-deficient mouse. ⁴ Eckes and colleagues have published similar results recently. ⁵