There are a number of issues that need to be dealt with before or during data collection in the field. We assume that the user has calibrated the equipment and decided on a deployment strategy. Depending on the acoustic unit used, there is also a number of collections settings that need to be specified. Some of these are not critical as they can be changed during data processing. But some cannot be changed later and will determine the vertical resolution and noise levels (pulse duration, power settings), and the smallest organism that can later be analyzed (e.g. collection thresholds). In addition, it is always important to document all information as well as unusual observations during the survey. Weather and moon light should be documented as well.