The present Ph.D. thesis investigated morphosynatctic and lexical-semantic aspects of German compound comprehension. Previous studies, on one hand, provide inconclusive evidence for semantic decomposition of nominal compounds during acoustic presentation (Isel et al., 2004; Pratarelli, 1995; Wagner, 2003). On the other hand, morphological effects of decomposition have only been investigated in the visual modality which cannot be generalised to the auditory modality (Andrews, 1986; Sandra, 1990; Zwitserlod, 1994). The purpose of the present experiments was to answer the question of whether and how compound constituents are accessed from the mental lexicon during auditory comprehension, i.e. whether or not compounds are decomposed