Technical Abstract: The accumulation of salinity in the soil root zone can have adverse effects on crop yields by making it more difficult for plants to extract water, by upsetting the nutritional balance of plants or causing toxicity by a specific ion (e.g., sodium), and by affecting physical properties of soils (e.g., tilth and permeability) that influence plant growth. Because of the potential detrimental impacts of soil salinity accumulation, it is a crucial soil chemical property to measure and monitor. The objective of this chapter in ASCE Salinity Manual #71 Agricultural Salinity Assessment and Management (2nd edition) is to provide a thorough discussion of the laboratory- and field-scale approaches for measuring soil salinity. The chapter covers the rationale and need for measuring soil salinity; methods of laboratory, lysimeter, and plot-scale soil salinity measurement with particular emphasis on the measurement of apparent soil electrical conductivity (ECa); edaphic factors influencing the ECa measurement; methods of field-scale soil salinity measurement with focus on ECa-directed soil sampling to map salinity at large spatial extents; soil sample designs based on geospatial ECa data; factors that must be considered when conducting an ECa survey; and use of remote imagery for measuring soil salinity at landscape scales. The chapter provides sufficient background and knowledge to guide soil scientists, agricultural engineers, resource specialists, agronomists, plant scientists, and agricultural consultants in applying the techniques available for measuring and monitoring soil salinity at local and field scales, whether to meet research objectives or real-world applications.