Underwater-radiated noise from commercial ships may have both short and long-term negative consequences on marine life, especially marine mammals. IMO’s Edward Kleverlaan, Head, Office for LC/LP & Ocean Affairs, has outlined IMO’s work on measures to reduce underwater noise, including the Guidelines for the reduction of underwater noise from commercial shipping to address adverse impacts on marine life (MEPC.1/Circ.833), at the World Organisation of Dredging Associations (WODA) Workshop on Underwater Sound in Relation to Dredging, in Paris, France (26 March).