A case-finding program for the identification of patients with familial hypercholesterolemia (FH) has been established in Spain. The program is based on family investigation and molecular genetic testing for mutations in the low-density lipoprotein receptor gene. To assist this program, intensive research into the molecular basis of FH and genotype/phenotype relations is performed. To optimize DNA testing, a DNA-diagnostic platform has been constructed that is composed of systematic mutation screening by single-strand conformation polymorphism (SSCP) analysis, DNA-sequencing, Southern blotting, and the use of microarrays for high-throughput analysis. To date, 161 different mutations leading to inherited hypercholesterolemia have been identified in Spanish patients with FH. In addition, a patient organization was founded to ensure patient support and follow-up. To further facilitate FH case-finding and patient follow-up, we initiated the publication of a set of guidelines for diagnosis and clinical management of FH that can be applied internationally.