Security of radioactive sources has been an issue since the earliest days of safety regulation of such materials. Since the events of September 11 2001, some governments and regulatory bodies have been much more focussed on these issues and have introduced extensive and enhanced security arrangements. International organisations like the IAEA and WINS have worked hard to help States in this regard. However, only a minority of States have implemented statutory security systems for radioactive source security. Why have so many States still to take action? What can be done to encourage and support these changes? This paper will offer some possible explanations for the lack of action in so many States and some potential answers to these questions.