This paper examines several types of R&D organization, including one noncooperative (independent R&D) form and three cooperative ones (R&D coordination, an R&D consortium and a research joint venture (RJV)). We consider the sharing of both research inputs and outputs in an R&D consortium and an RJV. We show that the superiority of a form of R&D organization cannot be determined uniquely, but should be judged by four parameters. In addition, it is shown that there exist possible mixes of these parameters in which an R&D consortium is superior to either R&D coordination or an RJV in terms of technological improvement and social welfare. JEL Classification Numbers: L13, L41.