This article reviews intellectual property rights (IPRs), with some emphasis on the protection of agricultural and life sciences innovations. The main institutional features of IPRs are first discussed, along with a brief historical background and an articulation of the main rationale for the existence of such rights. This is followed by an overview of the principal economic issues related to IPRs. The main benefit/cost trade-offs of allowing patents and other IPRs are explained, and specific issues are then analyzed in some depth, including the scope of patent protection, the effects of patent races, and the problems arising when IPRs concern cumulative and/or complementary innovations. The economics of IPRs are further illustrated by considering instruments alternative to patents, such as prizes and government procurement contracts. The article ends with a brief discussion of some open policy issues in this area.