Hydroacoustic technology has been used in a wide range of applications since the early 1900’s. The technology is available globally and is often used by recreational fishers to make qualitative assessments informing decision making. However, historically, this tool has also proven sufficiently powerful to perform quantitative scientific assessments of physical and biological underwater resources. Hydroacoustic technology operates on a level of efficiency unmatched by more conventional survey methods such as netting or electrofishing. In this assessment, four methods are examined for separate technologies – scientific split beam echosounders, recreational sidescan imaging, traditional 2D sonar and the more recent live scanning sonar. Each is considered for applications in habitat mapping and assessment, fish biomass estimates and fish behaviour assessments. Applications of vertical (down through the water column) and horizontal (across the water column) methods are compared. We discuss practical methods for planning surveys, collecting and cleaning data, and post processing and analysis suitable for monitoring, management and research applications. Samples of results from completed surveys are presented to demonstrate real-world applications.