The Lp(a) lipoprotein, a distinct class of serum lipoproteins, was detected in 1962. It consists of an LDL particle to which a long polypeptide chain is attached by a disulfide bridge. The level of Lp(a) lipoprotein is genetically determined. Single locus control was suggested already in the very first report, and this has been conclusively confirmed by the demonstration of absolute genetic linkage to the plasminogen gene, from which the LPA gene is likely to have evolved. The detection in 1974 of an association between Lp(a) lipoprotein and coronary heart disease has been confirmed in numerous studies. The Lp(a) lipoprotein may have atherogenic as well as thrombogenic properties and thus form the bridge between atherogenesis and thrombogenesis. Genes determining a moderate level of Lp(a) lipoprotein may be longevity genes, and it seems possible that Lp(a) lipoprotein, because of its affinity to vessel walls, may also influence placental function. Lp(a) lipoprotein measurements should be included in the diagnostic work-up of people with premature coronary heart disease or with such disease in close relatives.