1. Ocean mixing: oceanography at a watershed Alberto Naveira Garabato and Michael Meredith 2. The role of ocean mixing in the climate system Angélique V. Melet, Robert Hallberg and David P. Marshall 3. The role of mixing in the large-scale ocean circulation Casimir de Lavergne, Sjoerd Groeskamp, Jan Zika and Helen L. Johnson 4. Ocean near-surface layers Baylor Fox-Kemper, Leah Johnson and Fangli Qiao 5. The lifecycle of surface-generated near-inertial waves Leif N. Thomas and Xiaoming Zhai 6. The lifecycle of topographically-generated internal waves Ruth Musgrave, Friederike Pollmann, Samuel Kelly and Maxim Nikurashin 7. Mixing at the ocean's bottom boundary Kurt L. Polzin and Trevor J. McDougall 8. Submesoscale processes and mixing Jonathan Gula, John Taylor, Andrey Shcherbina and Amala Mahadevan 9. Isopycnal mixing Ryan Abernathey, Anand Gnanadesikan, Marie-Aude Pradal and Miles A. Sundermeyer 10.Mixing in equatorial oceans James N. Moum, Andrei Natarov, Kelvin J. Richards, Emily L. Shroyer and William D. Smyth 11.Mixing in the Arctic ocean Yueng-Djern Lenn, Ilker Fer, Mary-Louise Timmermans and Jennifer A. MacKinnon 12.Mixing in the Southern Ocean Sarah T. Gille, Katy L. Sheen, Sebastiaan Swart and Andrew F. Thompson 13.The crucial contribution of mixing to present and future ocean oxygen distribution Marina Lévy, Laure Resplandy, Jaime B. Palter, Damien Couespel and Zouhair Lachkar 14.New technological frontiers in ocean mixing Eleanor Frajka-Williams, J. Alexander Brearley, Jonathan D. Nash and Caitlin B. Whalen