Gangliosides are a group of glycosphingolipids that have at least one sialic acid residue. These lipids are structural and functional components of the external leaflet of the plasma membrane, particularly in neurons. Gangliosides together with cholesterol and sphingomyelin form lipid rafts that contain specific proteins involved in many important cellular processes, including signal transmission, cell growth and proliferation. Changes in the membrane gangliosides profile induce disturbances in the cell functions and finally lead to numerous diseases, mostly in the nervous system. The majority of such nervous system disorders can be recognized on the basis of analysis of the serum gangliosides profile and/or the presence of anti-ganglioside antibodies. Supplementation with exogenous gangliosides also seems to be a successful procedure for the recovery of ganglioside homeostasis in the neurolemma.