Many studies are focused on the distribution of populations and communities associated with environmental gradients. One of the greatest environmental gradients on this planet is that related to depth on the sloping parts of the floor of the ocean. However, the causes of the patterns found along these gradients remain one of the most difficult and elusive problems faced by deep-sea ecologists. Furthermore, there are few data on the depth-related distribution of the smaller animals. This project pursues a research on structural biodiversity (expressed as density, species composition and population structure of a community) of the hyperbenthic fauna along these depth gradients on continental slopes in different areas along the European coasts (Porcupine Seabight, Galicia Bank,...). This study also aims at investigating depth-related distribution of the hyperbenthic organisms on different taxonomic levels. With this research we hope to contribute to the inventory of the global biodiversity of marine hyperbenthic communities.