Contractual joint ventures, sometimes also called as “consortiums”, where several participants, without creating a new entity, unite their personal efforts and material resources with a view of achieving a certain common goal, remain a popular organizational form of large-scale international investment projects all over the World. In view of significant amount of their investments in these projects, any prospective foreign participants may wish to consider whether structuring their activities through a contractual joint venture would allow them to effectively protect their economic interests against possible adverse actions of a host State. Or, they should rather create a joint venture in the form of a partnership or a corporation under the laws of the project’s host State or under the laws of another country? To answer these questions, the article analyses the status of contractual joint ventures and their participants in international investment arbitration and compares it with the status of partnership and corporate joint ventures and their participants. The analysis is primarily carried out on the example of contractual joint ventures under Swiss law, because this law has been frequently chosen by participants of international investment projects as applicable law in a wide variety of international projects. Although the absence of legal personality of contractual joint ventures prevents them from acting as a claimant in both ICSID and non-ICSID investment arbitration, it does not by itself preclude individual claims of their participants in both types of arbitration. Furthermore, the comparison between possible amounts of participants’ individual claims reveals that under similar circumstances foreign investors in contractual joint ventures could potentially recover the same amount of damages as those in partnership and corporate joint ventures. On the basis of this comparison, the article argues that the use of contractual joint ventures would not put foreign investors in a disadvantageous position as concerns the possibility to protect their economic interests against an adverse action of a host State as compared with the participants in other two types of joint ventures.