Compounds such as bioactive proteins (pore-forming protein and tachylectin) from sponges may be used for antibacterial activity while skeletal elements such as biosilica serve as blueprints for new biomaterials applicable to biomedicine. In addition to a search for marine natural products, clearly the symposium and now the resulting issue have underscored the need for international cooperation as we continue to search for products with valuable applications to human health. The aim of this issue was to present recent advances in the discovery and development of marine natural products, which has laid the foundation for the synthesis of proteins, drugs, and other bioproducts with special functions.