A Cooperative Bargaining Solution for Priority-Based Data-Rate Tuning in a Wireless Body Area Network In this paper, we propose a cooperative game theoretic approach for data-rate tuning among sensors in a Wireless Body Area Network (WBAN). In a WBAN, the body sensor nodes implanted on a humanbody typically communicate through a capacity-constrained single channel. This is a serious concern because most applications in WBANs involve real-time data streaming and providing useful notifications and efficient feedback to the patients or other users according to their health conditions. To increase the Quality of Service (QoS), we need an efficient data-rate tuning mechanism, which tunes the data-rate of a sensor based on the criticality of health parameter measured through it. Our approach considers the unique features typical of WBAN applications, and provides a generalized solution for the problem. We propose a cooperative game theoretic approach, based on the Nash Bargaining Solution (NBS), which does not only provide priority-based tuning, but also maintains the fairness axioms of game theory. The proposed approach yields 10% average increase in data-rates for the sensor nodes that have critical physiological data to transmit. We also validate the approach through real system implementation with the help of real sensor devices such as heart rate sensor, and pulse oximeter.