Constructivism is regarded as increasingly important in International Relations. More often than not the approach is related to the issue of identity. constructivism and identity are, however, in a dangerous liaison. This article argues that Alexander Wendt's constructivism needs identity as a central concept but that this very concept threatens to undermine the possibility of his constructivism. It is further suggested that this problem has some relevance to other constructivist approaches positioned in the middle ground between rationalist and reflectivist theorizing. The argument is illustrated with a consideration of the debates around the redefinition of the role of the Federal Republic of Germany to include the possibility of German military involvement abroad.