This dissertation analyses the international and to some extent domestic regulation pertaining to trade in hazardous substances. Hazardous trade regulation is found to promote or accommodate three objectives in particular: the strengthening of the ability of (importing) States to exercise control of transboundary flows of hazardous substances; the protection of human health and environment; and the avoidance of impediments to the free flow of goods. The simultaneous pursuance of these objectives entails potential or actual conflicts. 
    

Among the regulatory instruments employed for controlling hazardous trade particular attention is given to prior informed consent (PIC) procedures. These have the potential to strengthen the effective sovereignty of importing States, i.e. their ability to make and enforce informed decisions with respect to import of hazardous substances. These procedures are also compared with export bans, import bans and export notification procedures. It is inter alia asked where different trade-restricting measures place the right to make decisions and whether that right is combined with any means by which such decisions may be enforced.
    

It is concluded that there is no general international law requirement for PIC for transboundary shipments of hazardous substances. Such a requirement may, however, with certain caveats be substantiated for hazardous wastes. It is also concluded that the effective operation of PIC procedures requires the availability of substantial resources in both exporting States and importing States. This may argue for the application of e.g. export bans to particularly hazardous substances. PIC procedures are on the other hand more flexible, better at empowering importing States and are also less likely to conflict with free-trade law compared to many bans. PIC is in itself no guarantee for a particular level of environmental protection.

Keywords: prior informed consent; PIC; trade bans; effective sovereignty; environmental law; free trade law; hazardous substances; waste; chemicals; genetically modified organisms.