This book reports on cutting-edge research and technical achievements in the field of hydraulic drives. The chapters, selected from contributions presented at the 21st International Scientific-Technical Conference on Hydraulic and Pneumatic Drives and Control, Centrifugal Pumps, Valves, and Seals, NSHP 2025, held on October 8-10, 2025, in Karpacz , Poland, cover a wide range of topics such as theoretical advances in hydraulics, pneumatics and control, fluid dynamics, diagnostics and simulation, and energy aspects and applications. Further topics include design and performance aspects of pumps and rotary systems, sealing elements and connections, and new materials and their properties in improving the efficiency of hydraulic components.