Language Learning ISSN 0023-8333 Morphological Structure in Native and Nonnative Language Processing Harald Clahsen University of Essex Claudia Felser University of Essex Kathleen Neubauer University of Essex Mikako Sato University of Essex Renita Silva University of Essex This article presents a selective overview of studies that have investigated how advanced adult second language (L2) learners process morphologically complex words. The stud- ies reported here have used different kinds of experimental tasks (including speeded grammaticality judgments, lexical decision, and priming) to examine three domains of morphological processing (regular and irregular inflection, derived word forms, and morphosyntactic phenomena) in L2 learners from typologically different first language (L1) backgrounds. The results from these studies demonstrate clear differences between native and nonnative processing in all three domains, indicating that adult L2 learners are less sensitive to morphological structure than native speakers and rely more on lexical storage than on morphological parsing during processing. Keywords morphological processing; event-related potentials; priming; inflection; derivation; morphosyntax; German; English Correspondence concerning this article should be addressed to Harald Clahsen, Department of Language and Linguistics, University of Essex, Wivenhoe Park, Colchester CO4 3SO, UK. Internet: harald@essex.ac.uk Language Learning 60:1, March 2010, pp. 21–43 21 C  2010 Language Learning Research Club, University of Michigan