General considerations; the energetics of charge transfer complexes; some techniques for identifying charge transfer complexes; fractals, irreversible thermodynamics, chaos, and feedback cycles; purines, pyrimidines, nucleosides, nucleotides, DNA, and RNA complexes; charge transfer complexes of aminoacids, proteins, and porphyrins; chapter charge transfer complexes of saccharide systems; charge transfer complexes of lipids, lipid systems, and vitamins; complexes of neurotransmitters and neuroleptics; charge transfer complexes in microorganisms; therapy and charge transfer complexes; retrospect, outlook and speculations.