Reduced-order models, substructuring techniques and uncertainty quantification are important aspects in computational dynamics, fluid-structure interactions, vibrations and vibroacoustics. In this framework, we will present the following new aspects: (i) Stochastic reduced-order model in low-frequency dynamics in presence of numerous local elastic modes, for which the high modal density makes the use of the classical modal analysis method not suitable; (ii) New ingredients useful for the nonparametric stochastic modeling of uncertainties (a) for structures with uncertain boundary conditions and/or coupling between substructures and (b) for linear viscoelastic structures in the medium-frequency range; (iii) Bayesian posteriors of uncertainty quantification in computational structural dynamics for low- and medium-frequency ranges. In addition to some illustrations which will be given, three industrial applications will be presented