This book gathers select proceedings of the 16th International Conference on Vibration Problems (ICOVP) & 11th International Conference on Wave Mechanics and Vibrations (WMVC), held in Lisbon, Portugal, on September 2-5, 2025. It covers recent developments and cutting-edge methods in wave mechanics, wave propagation, and vibrations applied to a wide range of engineering problems. It presents analytical and computational studies in structural mechanics, vibrations of transport systems, vehicle dynamics, seismology and earthquake engineering, structural health monitoring, acoustics, aeronautics, robotics, and nuclear engineering among others.