Familial hypercholesterolemia is a common, yet often underdiagnosed, genetic disease. Nevertheless, this condition is easily manageable provided that the disease is detected early enough and appropriately treated. Our article presents some diagnostic tools for this condition. In a first patient of an as yet unexplored family, referred to as the index patient, we propose to use the DLCN (Dutch Lipid Clinic Network) score, which should be followed by genetic analysis, depending on the case. Once the diagnosis has been confirmed in this index patient, the disease can easily be identified in other first-degree relatives based on a reference table that has presented in this article. This table provides the threshold values of LDL cholesterol concentrations, according to age and gender, at which the existence of familial hypercholesterolemia in a first-degree relative should be suspected. To this article, we have attached a sample letter that can be addressed to family members, designed to alert them on this disease and facilitate the work-up of their general practitioners.