Bioorganometallic Chemistry has become a mature area of science and is comprehensively covered by leading experts in this book. Naturally occuring bioorganometallic complexes, such as vitamin B₁₂ and recently discovered iron and nickel hydrogenases, including a possible role of the latter in the geochemical theory of the origin of life, are considered. The possible formation of carbene complexes of cytochrome P450 enzymes in various metabolisms of xenobiotics is also discussed. The bioorganometallic chemistry is considered to provide not only organometallic receptors such as polynuclear organometallic macrocycles for biologically interesting molecules but also ferrocene-peptide bioconjugates giving a peptidomimetic basis for protein folding. The medicinal properties of organometallic compounds are reviewed, with notable applications in the treatment and diagnosis of cancer and in the treatment of viral, fungal, bacterial and parasitic infections. Therefore the reader will get a balanced view of this rapidly developing and promising area.