Defense of Benthic Invertebrates Against Surface Colonization by Larvae: A Chemical Arms Race -- Furanones -- Isocyano Compounds as Non-Toxic Antifoulants -- 3-Alkylpyridinium Compounds as Potential Non-Toxic Antifouling Agents -- 5, 6-Dichloro-1-methylgramine, a Non-Toxic Antifoulant Derived from a Marine Natural Product -- Biofilms -- Adrenoceptor and Other Pharmacoactive Compounds as Putative Antifoulants -- State-of-Art Methodology of Marine Natural Products Chemistry: Structure Determination with Extremely Small Sample Amounts. Increasing awareness of the deleterious effects of toxic components in antifouling coatings has raised interest in the potential for nontoxic alternatives. This book examines how marine organisms from bacteria to invertebrates and plants use chemicals to communicate and defend themselves. Chemicals that prevent colonisation of living surfaces are particularly pertinent to antifouling technology and may inspire new solutions. The challenge is to identify such compounds, identify the means for sustainable production and incorporate them into coatings to give long-term antifouling efficacy.