Major changes in national seed systems, including the rapid development of commercial seed enterprises, the growth of non-governmental organization (NGO) seed projects, and the concomitant decline of public sector seed provision, call for a re-examination of seed regulatory frameworks in developing countries. Privatization and deregulation are often presented as logical partners, but the nature of seed system change and the complexities of regulatory responsibility make seed regulatory reform less straightforward than it first appears. Challenges include the limited opportunities for commercial seed development, the need to provide guidance to seed systems in transition, the international pressures for plant variety protection (PVP), and significant differences among various national regulatory approaches. Problems with the conduct of current seed regulations include significant inefficiency, the use of inappropriate standards, inadequate opportunities for the participation of new entrants to the seed system, and a lack of transparency. Specific guidelines are offered for: reorganizing variety registration and performance testing; providing a balanced opportunity for PVP; and broadening participation in seed quality control. National seed regulatory agencies will see their role shift from the direct supervision of seed production towards technical and policy support for the development of a wider range of seed provision options.