Book excerpt: This publication, a collection of 174 papers, encompasses the fundamental and intricate photochemistry and electron transfer of flavins and flavoproteins, the mechanisms associated with enzymes utilising flavins (such as dehydrogenases, reductases, oxidases, monooxygenases, synthases, peroxidases), the three-dimensional structures of flavoproteins and flavoenzymes and the emerging role of flavins and flavoproteins in medicine. Flavins and Flavoproteins 1996 continues the series which has appeared every three years since 1965. Presented are overviews of key areas of flavin research, coupled with the most recent understanding of the chemistry/photochemistry of flavins and the structure/function relationship of numerous proteins/enzymes that use flavins as essential cofactors. Key Features: Detailed studies on the structure and mechanism of flavoenzymes are reported together with newly discovered medical aspects; New research of high quality with extensive data, figures and bibliographies; The interaction of flavins with other electron carriers such as the cytochromes, metals, and non-heme iron centres is investigated with a variety of spectrophotometric techniques; NMR and crystallography studies have provided new three-dimensional structures of several flavoenzymes and flavoproteins; Numerous papers on an extensive number of flavoenzymes and complex flavoproteins are presented.