This volume contains a collection of recent papers on FreeLogic which cover a wide range of topics. These topics show that FreeLogic is applied not only in traditional philosophical areas, but also in various contexts of modern formal logic as well as in the discussion of theoretical aspects of programming. Part I of the book covers theories of names and definite descriptions.Part II contains papers on various topics in the logic of modalities.Part III is devoted to semantics and programming. In part IV FreeLogic is used to analyse and discuss topics from the history of philosophy. In addition, one of the founders of Free Logic, KarelLambert, not only contributes an article to this volume, but he also comments the papers of all the other authors. So this book will be of interest not only to philosophers and logicians, but also to computer scientists and researchers interested in foundational aspects of computer programming. CONTENTSPreface. Free Logic: A Fifty-Year Past and an Open Future;E. Morscher, P. Simons. Part I: Names and DefiniteDescriptions. Free Logic and Definite Descriptions; K.Lambert. Calculi of Names: Free and Modal; P. Simons. PartII: Modalities. Free Logic and uantification in Syntactic ModalContexts; P. Schweizer. Substitution, uantifiers and Identity in Modal Logic; S. Ghilardi. Free Epistemic Logic; W.Lenzen. Part III: Semantics and Programming. SupervaluationalFree Logic and the Logic of Information Growth; J.B.Escriba. `No Input, No Output' Logic; S. Lehmann.Free Logic in Program Specification and Verification; R.D. Gumb.Part IV: History. Existence and Reference in Medieval Logic;G. Klima. Can Meinongian Logic Be Free?; J.Pasniczek. Part V: Comments. Comments; K.Lambert. Index of persons.