In this paper we consider whether one type of individual investor, which we call at risk investors, should be denied access to securities markets to prevent them from suffering serious financial harm. We consider one kind of paternalistic justification for prohibiting at risk investors from participating in securities markets, and argue that it is not successful. We then argue that restricting access to markets is justified in some circumstances to protect the rights of at risk investors. We conclude with some suggestions about how this might be done.