This document provides guidance for the addition of acoustic observations to the Global Ocean Observing System (GOOS) through implementation of the Ocean Sound Essential Ocean Variable (EOV). The goal of this Ocean Sound EOV Implementation Plan is to define a baseline of how ocean sound observations are collected, analyzed, managed and reported. The Implementation Plan has been produced by a Committee of the International Quiet Ocean Experiment (IQOE), a project co-sponsored by the Scientific Committee on Oceanic Research (SCOR) and the Partnership for Observation of the Global Ocean (POGO).