This is the first complete edition of \"Das Büchlein der Gesundheit\", based on Trieste, Biblioteca Civica Attilio Hortis, MS 2-25, written in a late fifteenth-century Bavarian dialect. It is an excellent representative of the popular genre of the \"regimen sanitatis\", a practical compendium of predominantly preventive medicine. It consists of six tractates: Tractate I, on the four seasons, the four complexions and the twelve months of the year; Tractate II, on the non-naturals; Tractates III-V, on individual foodstuffs; Tractate VI, on mainly medicinal plants, on \"branntwein\", and on fevers, dysentry, menstruation, and the plague.