This article reviews current data on the use of cognition enhancers as study aids in the student population. It identifies gaps and uncertainties in the knowledge required to make a balanced assessment of the need for some form of regulation. The review highlights the weak evidence on the prevalence of use of such drugs, especially outside the US, and the ambiguous evidence for their efficacy in a healthy population. Risks are well documented for the commonly used drugs, but poorly appreciated by users. These include not only the side-effects of the drugs themselves, but risks associated with on-line purchase, which offers no guarantees of authenticity and which for some drugs is illegal. The case for urgent action to regulate use is often linked to the belief that new and more effective drugs are likely to appear in the near future. The evidence for this is weak. However, drugs are not the only possible route to neuroenhancement and action is needed to collect more data on the impact of existing drugs, as well as new technologies, in order to guide society in making a proportionate response to the issue. This article is part of a Special Issue entitled 'Cognitive Enhancers'.