The paper discusses the adequate role of ideal theory for the discussion of practical problems. Therefore, I will reconstruct the Rawlsian understanding of the ideal-theoretical method and confront it with the critiques of Raymond Geuss and Amartya Sen. While Geuss is sceptical, whether ideal theory provides an appropriately critical perspective, Sen doubts the practical usefulness of ideal-theoretical models. It will be shown, that Rawlsian ideal theory can deal with these criticisms and that it is a useful tool for solving practical (...) problems. (shrink)