The International Conference on Structural Engineering Dynamics (ICEDyn 2025) has the objective of bringing together various subjects that may be understood as part of a whole big area of Structural Engineering Dynamics. It is indeed a vast area, which comprehends not only Mechanical Engineering but also Civil, Aeronautical and other akin disciplines. All subjects are welcome within this big umbrella, although the organisers would like to give relevance to some topics in particular, to orient the possible attendees and provide some guidelines. In what structural dynamics is concerned, the main topics considered here have to do with experimental and operational modal analysis and testing, validation and updating of numerical models, new developments in experimental techniques, modelling of damping, structural health monitoring, substructuring, active control, smart materials, nonlinear dynamics, railway dynamics, rotating machinery and vibro-acoustics. It is anticipated that the conference will appeal to a very wide range of disciplines, from aeronautical and civil engineering structures to all forms of machinery. The organisers expect that the conference may be run in two or at most three parallel sections to avoid dispersion and help congregating people to fruitful and nice interactive discussions.