The workshop Production-Comprehension Asymmetries in Child Language held in Osnabruck in 2009 is the starting point for this book. The workshop developed from the observation that children's production skills appear to precede their comprehension skills in a number of phenomena, e.g. pronouns or negation. The volume provides cross-linguistic evidence for such asymmetric development and investigates grammatical and methodical explanations of the observed asymmetries. Language acquisition is a human endeavor par excellence. As children, all human beings learn to understand speak at least one their mother tongue. It is a process that seems to take place without any obvious effort. Second language learning, particularly among adults, causes more difficulty. The purpose of this series is to compile a collection of high-quality monographs on language acquisition. The series serves the needs of everyone who wants to know more about the problem of language acquisition in general and or about language acquisition in specific contexts.