The board of directors of joint stock company can take decisions by holding a meeting or -if the conditions stipulated in Turkish Commercial Code Art. 390.4 are present- decisions can be taken without holding a meeting. In order for the board of directors to take a valid decision by holding a meeting, first of all, the call for the meeting where the decision is taken must be made by authorized persons. In this study, first of all, in case the board of directors takes decision by holding a meeting, evaluations will be made regarding the determination of who is/are authorized to call the board meeting. In this context, the issues of who can make the call, especially whether there exist situations and conditions where the members of the board of directors can make a call directly, whether it is possible to make arrangements that give direct call to the members, and which body/s may be authorized to make these arrangements will be discussed and clarified by revealing the opinions in the doctrine. Following the determination of the authorized/s to convene the board of directors for a meeting, the legal fate of the decisions taken by the board of directors convened upon the call made by unauthorized persons, in other words, whether the aforementioned decisions will result in nullity or absence, will be scrutinized within the framework of the views put forward in the doctrine and judicial decisions and evaluations will be made in this regard.