The first reports of familial cardiac disorders appeared over 60 years ago. Since then, knowledge on cardiogenetic disorders has increased tremendously. And now cardiogenetics is a rapidly expanding field, including the familial cardiomyopathies, arrhythmias, congenital heart diseases and cardiovascular disorders. Most of these disorders have an autosomal dominant inheritance pattern. In the last decade many genes involved in these disorders have been identified and more discoveries are sure to follow. The growing insight in the genetic conditions of the cardiovascular system has led to a substantial increase in the number of patients referred to clinical genetic departments for genetic counselling and DNA diagnostics. Close collaboration of departments of cardiology and genetics resulted in the initiation of multidisciplinary cardiogenetic outpatient clinics to provide the optimum care and facilitate family studies of hereditary cardiologic conditions. This way family studies of more and more adult patients could be initiated which led to increasing numbers of at risk relatives visiting the cardiogenetic units. Similarly, the cardiogenetic units were involved in counselling and family studies of the families of paediatric patients. Over the years the total number of cardiogenetic counselling sessions rose from 53 in 2000 to 482 in 2008 at the department of clinical genetics of the Erasmus Medical Centre in Rotterdam. In 2007 that number made up 12.6% of the total number of counselling sessions in Rotterdam. This is not only a local trend, it is observed nationwide. According to the numbers of the Dutch Society of Clinical Genetics (VKGN) the number of cardiogenetic counselling sessions rose from 538 in 2000, representing 4.5% of the total amount of counselling sessions, to 3216 in 2008, rising to 11.8% of all counselling sessions.