Dissolved oxygen (DO) is essential to many marine organisms and is an important parameter in assessing water quality and ecosystem health. Recently, there has been growing evidence that global ocean DO concentrations are decreasing (Schmidtko et al., 2017), with this trend being enhanced in the coastal ocean (Gilbert et al., 2010). We invite presentations on the physical and biological processes affecting dissolved oxygen in the ocean, particularly in coastal and shelf seas. This will be a multidisciplinary session, and we encourage both observational and numerical studies.