Lauri Karttunen has done groundbreaking work in theoretical and computational linguistics. The papers in this volume present new, state-of-the-art work building on his numerous contributions. The first part includes papers on formal semantics, the focus of Karttunen's early career to which he has returned in recent years. The second part provides a natural extension of his semantic work: the formal analysis of meaning and reasoning and the integration of the lexical and ontological components to enable reasoning by computational systems. The third part focuses on syntactic analyses, including the structure of non-finite clauses and sentence embedding predicates and factivity. The final part of the volume deals with finite state methods and grammars, reflecting Karttunen's extensive contributions to finite state theory and technology and its application to natural language.