The ocean floor is covered by sediments, thus marine benthos is one of the largest single habitats on Earth. Yet, the total area of sediment habitat that has been sampled is infinitesimally small. This is likely because the main method to sample the bottom relies on single point samplers such as grabs and cores. Larger areas are sampled by dragging dredges, sledges, and trawls. Coring devices, particularly multicorers, are recommended for sampling infauna because the vertical structure of the sediment is maintained during sampling. Infauna then have to be extracted from the sediments with sieves and washing techniques, making it very labor intensive to study marine benthos. This kind of bottom sampling provides information that is limited to benthic community structure. Sediment profile imaging systems can also provide information on benthic community function. Benthic indicators of ecosystem health is a very common way to perform environmental assessments in both environmental risk analyses and environmental effects analyses. Sampling designs should always be balanced, and control for confounding factors. A minimum of three replicate samples should be collected when the study design is based on station comparisons. In contrast, if mapping to elucidate spatial variability is the main goal, then one replicate at more stations can be more robust.