The study looks at comparison structures in German formed with the particles als and wie. On the basis of a corpus of written language, the usage modes of the two particles traditionally described as 'comparative' are subjected to close syntactic and semantic analysis. Theories of generative grammar are contrasted with empirical data and found to be ungrounded. Finally a new systematization for German comparison structures with als and wie is proposed. This study fills a research gap that has obtained for many years.