This article discusses the emergence and contours of farmers' rights to save, use, exchange and sell farm-saved seeds and other propagating materials, including from protected plant varieties, enshrined in Article 9 of the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA) to modulate the exclusive rights of patent and plant variety certificate holders. Second, the article raises the challenges of transposing farmers' rights to seed practices into national legislation to make these rights effective and enforceable. Indeed, when transposing these rights, World Trade Organization (WTO) member states must act within the scope of Article 27:3(b) of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS Agreement), which establishes international obligations for the protection of plant varieties through intellectual property rights. Finally, this paper argues that the adoption of sui generis plant variety protection legislation, as enshrined in both Article 27.3(b) of the TRIPS Agreement and Article 9 of the ITPGRFA, is a means of ensuring the coexistence at the national level of the international regime of farmers' rights and the international regime of intellectual property rights on plant varieties, as well as a solution to recognize the plurality of plant variety breeding methods and practices.