At a rapid pace, in vitro diagnostic medical devices are being developed to detect risk factors for disease; to a growing extent, these test kits are also directly marketed to the public for use at home. While at first sight serving a good cause, self testing may have considerable drawbacks relating to the well-being of the test subject on the one hand, and to the privacy and the right not to know of other persons on the other. This raises the question whether the availability of self tests should be restricted. Taking into account legal developments in The Netherlands and the European Union, the author argues in favour of restrictions, at least when serious diseases or conditions are concerned. The existence of the internet is not an excuse for not adopting such safeguards.