Previous symposia on Metabolic Interconversion of Enzymes were held in 1970 (Santa Margherita-Ligure, Italy), 1971 (Rottach-Egern, Ger- many), 1973 (Seattle, USA) and 1975 (Arad, Israel). The present pub- lication reports the proceedings of the 5th International Symposium on Metabolic Interconversion of Enzymes, held in Titisee/Black Forest (Germany) from October 1st-5th, 1980. In the last few years, the number of enzymes for which control of activity by enzyme-catalyzed covalent modification, i.e., by intercon- version, is of recognized metabolic importance has increased so much that is was...