This textbook combines in a unique concept the design and construction of radial and axial fans with the problem of noise generation as well as its mitigation already in the fan development stage. The aim is to describe selected, easily applicable methods of aerodynamic design and noise prediction and to demonstrate their physical principles. Exercises with solutions facilitate understanding. The completely revised and expanded edition now also includes guidance on selecting fans for a given task, simulation-based optimization methods for fan design, and psychoacoustic methods that can be used to measure the quality of fan noise. This book is a translation of the original German 4th edition Ventilatoren by Thomas Carolus, published by Springer Fachmedien Wiesbaden GmbH, part of Springer Nature in 2020. The translation was done with the help of artificial intelligence (machine translation by the service DeepL.com). A subsequent human revision was done primarily in terms of content, so that the book will read stylistically differently from a conventional translation. Springer Nature works continuously to further the development of tools for the production of books and on the related technologies to support the authors.