The protection under intellectual property rights (IPRs) of traditional and indigenous knowledge (TK) has received growing attention since the adoption of the Convention on Biological Diversity (CBD) in 1992. Numerous contributions by academics, NGOs and governments have considered the need to provide some form of protection to TK. However, significant divergences exist as to whether IPRs should be applied and, if that were the case, which would be the rationale and modalities of protection. First, it is necessary to understand the importance and scope of TK – which includes its widespread use in traditional medicine and farming – and this is described in Section 1, along with the question of its definition. The starting point for any discussion about possible forms of protection should then be to clarify why there is a need to protect it, and what can be achieved. In Section 2, the main arguments for protection are considered under the headings of equity, conservation, preservation of traditional lifestyles, prevention of biopiracy, and promoting the use of TK and its importance in development. IPRs, as a legal tool, may be appropriate and efficient under certain circumstances, but inadequate or ineffective in others. For example, the recognition or establishment of new types of IPRs on TK may reduce rather than promote the use of such knowledge (eg in medicines or in the exchange of farmers’ materials) and policy-makers need to balance the expected benefits against the cost of such limitations. Another problem for some opponents is the essential incompatibility between the concepts of western IPRs and the practices and cultures of local and indigenous communities. Thus, since different objectives (such as equity, conservation, preventing misappropriation, etc) may be sought when the “protection” of TK is pursued, a basic point is the extent to which particular forms of IPRs may be suited or not to reach the objectives. Different strategies may be followed to protect TK under IPRs, including the application of existing modes of protection, the development of a sui generis regime, or a combination of both. These are described in Section 3, as is another option - the enforcement of customary laws which, in some cases, recognise certain forms of ownership over TK. Also mentioned here are concerns about the feasibility, effectiveness, costs and acceptability of possible legal systems for traditional and indigenous communities. Alternatively, protection may be seen as a mechanism to prevent third parties from unduly appropriating TK - the misappropriation option described in Section 4. The development of a misappropriation regime requires the documentation of TK, the ability to prove the origin of resources used in IPRs claims, and a requirement for consent from its traditional owners. In any case, the difficulties of effectively enforcing rights may be significant and dilute the value of any legal approach. The issue of TK protection has been dealt with in some national laws and constitutions. A clear legislative pattern, however, does not arise so far. Debates have also taken place in different international fora, where numerous studies and proposals have been made, which are discussed in Section 5. Despite all these efforts, many questions about objectives, tools and feasibility of TK protection remain unanswered. While work on the subject needs to be pursued – with the participation of the intended beneficiaries – attention to legal protection should not overshadow the fact that the access to land and the preservation of the communities’ own lifestyles, are indispensable conditions for the preservation and further development of TK. Section 6 summarises this paper’s conclusions. It also recommends that it seems premature to promote international IPRs-type standards for TK protection at present and suggests global rules to prevent misappropriation of TK. It also suggests various ways in which Overseas Development Assistance can be used to clarify and improve the present situation.