Joint ventures (JVs) are a common form of inter‐firm collaboration and, unsurprisingly, the subject of a vast literature, extending from economics to management and business studies. Issues of control are central to the definition of JVs, and this naturally calls for an interpretation in the context of the property rights theory (PRT) of the firm. In a series of seminal papers, Grossman, Hart and Moore (GHM) offer a rigorous framework to predict the allocation of control rights. Notably, under the standard assumptions of GHM, JVs are suboptimal. However, JVs are not suboptimal in more general settings where a number of the original framework's assumptions are relaxed. In the context of PRT, this paper surveys more than 20 contributions that address the optimality of JVs under contract incompleteness. The surveyed papers question the assumptions of GHM and reveal the circumstances in which JVs outperform sole ownership. Although contributions are scattered over time and bibliographical sources, we believe sufficient material has accumulated over 25 years of economic modelling to encourage some systematization. The discussion is organized in an intuitive and non‐technical way; in particular, effort is devoted to analysing each paper in detail and providing a unified framework.