David Farmer is widely regarded as a world leader in the use of acoustics to study the oceans, through both the development of instrumentation and the interpretation of data. His work has led to new insights on air–sea interaction and gas exchange in storms, particularly through the tracking of breaking waves and the mapping of bubble clouds using a self-contained Doppler imaging sonar. He has made important contributions to research in the Arctic by elucidating the fracturing of Arctic ice through acoustic measurements. He has pioneered the measurement of channel flows using acoustic scintillation. David has also made major contributions to the measurement and understanding of stratified exchange flows, such as that through the Strait of Gibraltar. He has received four patents, the Walter Munk Award and the Rosenstiel Prize as well as other recognition.