TNO is a leading Dutch organization for Applied Scientific Research, founded by Dutch law in 1932. TPD was one of its institutes focused on Technical Physics. Applied acoustics research at TPD started in 1941 in close cooperation with the Technical University in Delft. Initially it mainly covered room and building acoustics, extending in the subsequent years to environmental noise, ship and machinery acoustics. The research combined experimental work and modelling, often resulting in contributions to guidelines, legal regulations and (international) standards. The source-transmission-receiver chain was a common starting point, resulting for instance in measurement methods for source description, reciprocal methods, sound transmission prediction models and appropriate quantities and - in close cooperation with other TNO institutes - allowable levels for noise annoyance. The nature and impact of applied acoustics research will be highlighted, showing some examples from the fields of building acoustics, outdoor sound propagation of road, railway and shooting noise, structure-borne sound source characterization and transmission for ship acoustics and machinery noise. Finally a view will be given on the links to current and future research in this context.