Lipoprotein (a) [Lp (a)] is a low density lipoprotein (LDL) disulfide-linked to apolipoprotein (a) [apo (a)] and considered to be an independent risk factor for atherosclerotic cardiovascular disease. Apo (a) has a high homology with plasminogen, which has stimulated a lot of interest in the mechanism of atherogenicity and thrombogenicity of this lipoprotein. Recent advances in this mechanism were reviewed. We are still unclear about the physiological role of Lp (a). This research aspect must receive attention in the future. Furthermore, the most pressing need is for drugs that will lower serum Lp (a) concentrations.