One main goal of the recently finished FWF funded project “Cross-layer pronunciation models for conversational speech” was to investigate interdisciplinary approaches towards studying pronunciation variation and to show how researchers in the fields of automatic speech recognition, psycholinguistics and phonetics/phonology can profit from integrating findings of the respective fields. Such new approaches, covering all mentioned disciplines, are presented in the book “Rethinking Reduction”. The book contains 11 peer reviewed chapters, of which two are overview chapters written by the editors, and 9 contain original research. With “Reduction” we refer to acoustically reduced words. In natural conversations, for instance, a word like “yesterday” might be pronounced as yeshay, and a word like “haben” might be pronounced like ham. Phonetically reduced forms are extremely plentiful (e.g., 62% of word tokens in spontaneous Austrian German conversations are reduced), theoretically interesting (e.g., how do people learn to produce and understand the multiple reduced pronunciation variants existing per word?), and a key challenge for automatic speech recognition systems (e.g., new methods for acoustic and pronunciation modelling are needed). Despite the high frequency of reduced pronunciation variants, the canonical forms are still central to models of production and perception. Drawing from different fields and diverse languages, this volume brings new insights to the debate on abstractions and canonical forms in linguistics: their psychological reality, descriptive adequacy, and technical implementability.