There is an increasing interest of pharmaceutical industry in the natural environment as a source for new lead compounds. This interest is based on the fact that the chemical diversity of natural bioactive compounds is much higher than that of compounds synthesized by standard combinatorial chemistry. A successful drug discovery heavily relies on the coordinated multi-disciplinary effort of highly qualified researchers with special skills in different disciplines. There is, however, an urgent need for training of such researchers in Europe. The aim of the proposed Marie Curie research training network, arising from existing national centers of excellence in molecular biotechnology, high-throughput screening, drug development and chemoecology is a progressive and durable integration of the EU research capacities in bioprospecting, making Europe to a leader in this field. This network will utilize the unique ability of aquatic invertebrates to synthesize a large variety of bioactive compounds for medicine, plant protection and other applications. In addition to low-molecular-weight bioactive secondary metabolites, this network will search for high-molecular-weight proteins and enzymes with unique functions of industrial or medical interest. The specific structure of this network will allow enforcing the integration of the partners working on a wide range of taxa. The proposed training and transfer-of-knowledge programme will result in the generation of new knowledge, used by an innovative enterprise, whose participation underlines the economic and societal value of aquatic molecular biodiversity.