Acknowledgments -- Simplicity, simplification, complexity and complexification: where have the interfaces gone? / Enoch O. Aboh and Norval Smith -- Part I. Morphophonology. Initial vowel agglutination in the Gulf of Guinea creoles / Tjerk Hagemeijer -- Simplification of a complex part of grammar or not? What happened to KiKoongo nouns in Saramaccan? / Norval Smith -- Reducing phonological complexity and grammatical opaqueness: Old Tibetan as a lingua franca and the development of the modern Tibetan varieties / Bettina Zeisler -- Part II. Verbal morphology. Verb allomorphy and the syntax of phases / Tonjes Veenstra -- The invisible hand in creole genesis: reanalysis in the formation of Berbice Dutch / Silvia Kouwenberg -- Complexification or regularization of paradigms: the case of prepositional verbs in Solomon Islands Pijin / Christine Jourdan -- Part III. Nominals. The Mauritian Creole determiner system: a historical overview / Diana Guillemin -- Demonstratives in Afrikaans and Cape Dutch Pidgin: a first attempt / Hans den Besten -- Part IV. The selection of features in complex morphology. Contact, complexification and change in Mindanao Chabacano structure / Anthony P. Grant -- Morphosyntactic finiteness as increased complexity in a mixed negation system / Peter Slomanson -- Contact language formation in evolutionary terms / Umberto Ansaldo -- Part V. Evaluating simplification and complexification. Economy, innovation and degrees of complexity in creole formation / Marlyse Baptista -- Competition and selection: that's all! / Enoch O. Aboh -- Complexity and the age of languages / Umberto Ansaldo and Sebastian Nordhoff -- Part VI. Postscript. Restructuring, hybridization, and complexity in language evolution / Salikoko S. Mufwene.