Results of complex and integral investigations dedicated to the study of laws of glomerulonephritis evolution are presented, including retrospective analyses, statistical data, and longitudinal observations according to clinical, functional, immunological and morphological indices. The most important factors (etiology, variant, prolonged course, hypertension, morphological type, relative percentage of involved glomeruli) determining the evolution of acute and chronic forms of glomerulonephritis, such as clinical type, variant, morphological type, relative percentage of involved glomeruli, are pointed out. Further determining factors are sex, age of the patients, irrational treatment, intercurrent infections and nidi. The authors believe that the evolution of glomerulonephritis is determined by the state of the immune system and also by metabolic and functional disturbances.