This book reports on advanced theories and methods aimed at characterizing the dynamics of non—ideal compressible fluids. A special emphasis is given to research fostering the use of non—ideal compressible fluids for propulsion and power engineering. Both numerical and experimental studies, as well as simulations, are described in the book, which is based on selected contributions and keynote lectures presented at the 2nd International Seminar on Non—Ideal Compressible—Fluid Dynamics for Propulsion & Power. Held on October 4—5 in Bochum, Germany, the seminar aimed at fostering collaborations between academics and professionals. The two perspectives have been gathered together in this book, which offers a timely guide to advanced fundamentals, innovative methods and current applications of non—ideal compressible fluids to developing turbomachines, and for propulsion and power generation.