PURPOSE OF REVIEW: Despite being both the longest known and the most prevalent genetic risk marker for atherosclerotic cardiovascular disease (CVD), little progress has been made in agreeing a role for lipoprotein (a) [Lp(a)] in clinical practice and developing therapies with specific Lp(a)-lowering activity. We review barriers to progress, and discuss areas of controversy which are important to future research. RECENT FINDINGS: Epidemiological and genetic studies have supported a causal role for Lp(a) in accelerated atherosclerosis, independent of other risk factors. Progress continues to be made in the understanding of Lp(a) metabolism, and Lp(a) levels, rather than apolipoprotein (a) isoform size, have been shown to be more closely related to CVD risk. Selective Lp(a) apheresis has offered some evidence that Lp(a)-lowering can improve cardiovascular end-points. SUMMARY: We have acquired a great deal of knowledge about Lp(a), but this has not yet led to reductions in CVD. This is at least partially due to disagreement over Lp(a) measurement methodologies, its physiological role and the importance of the elevations seen in renal diseases, diabetes mellitus and familial hypercholesterolaemia. Renewed focus is required to bring assays into clinical practice to accompany new classes of therapeutic agents with Lp(a)-lowering effects.