Inadequate family communication concerning hereditary lipid disorders by index patients (IPs) may prevent their biological relatives from seeking testing and treatment. This lack of disclosure places the relatives at increased risk for cardiovascular disease. The present study, undertaken in the Netherlands, explored the reasons for family disclosure, and how disclosure was approached. Semi-structured interviews with 20 purposely sampled IPs revealed that they generally alerted their first-degree relatives of the genetic risk because they felt morally obliged to do so or because they were advised to do so by a health professional. However, IPs rarely alerted their more distant relatives due to insufficient risk knowledge or fear of being perceived as interfering in their relative's affairs. Furthermore, many IPs stated that they would not seek to persuade a relative to undergo testing out of respect for their autonomy. However, the findings did suggest that less direct methods were used for persuasion. An example would be stressing the severity of the condition. Consequently, the self-reported disclosures were incomplete and unbalanced. Typically, IPs provided information regarding the threat of inherited high cholesterol without furnishing information on means of coping with the risk. As IPs want and need professional support to help them disclose this information to their relatives, we suggest additional research about the ethical, practical and economic possibilities for this support.