D2S International is an industrial engineering and research company specialised in dynamics as it relates to stress, fatigue, noise, vibrations, annoyance and legislation. Our activities can be segmented into railway, building and environmental and numerical simulations. The railway segment focuses on noise and vibration impact studies with special attention to the track design and its interaction with the infrastructure (bridges, tunnels,) aimed at minimising airborne noise as well as ground borne noise and vibrations. When dealing with annoyance issues such as corrugation, squeal noise and impact noise from turnouts, public transport operators benefit from knowledge gained by D2S in its role of coordinator of major European research projects on these subjects. D2S Intl prides itself at proposing cost effective solutions that are also low maintenance and thus contributes to low life cycle costs. Building and environment centres on the acoustical comfort in buildings with special attention to the minimisation of noise from technical installations or ground borne noise entering the building through its foundations. In addition, offices, meeting rooms and auditoria are studied to optimise their sound qualities for their intended use. Numerical simulations applies a wide variety of engineering software to study the mechanical behaviour and the interaction of structures and systems in a variety of applications in the automotive, marine, railway and heavy industry.