Current approaches to the treatment of homozygous familial hypercholesterolemia (FH) are not optimal and this disorder remains an excellent candidate for the development of clinical gene therapy. Preclinical proof of principle studies of long-term expression of both the low density lipoprotein (LDL) receptor and the very low density lipoprotein (VLDL) receptor in relevant animal models of homozygous FH demonstrating reduction in both LDL cholesterol and atherosclerosis have been performed. The major rate-limiting step in the development of clinical trials is the development of safe vectors that provide long term expression. Once these vectors are available, effective clinical gene therapy for homozygous FH is likely to become a clinical reality.