—The plethora of applications for Wireless Sensor Networks (WSN) has experienced significant growth in recent years. Every application has a different set of requirements and it is highly desirable for all of them to share the available resources in an optimized way. The IEEE 802.15.4 standard for WSN includes guaranteed time slots (GTS) to schedule QoS demanding applications. However, the standard does not provide any type of QoS GTS scheduling mechanism and the authors are unaware of any other work that provides for service differentiation based GTS scheduling. We propose DSeDGAM, a novel dynamic service based differentiation GTS allocation mechanism to provide QoS and service based differentiation for WSN applications. Our solution takes into account static and transient aspects of QoS provisioning in WSN to construct a dynamic scheduling method. This work demonstrates that D-SeDGAM provides significantly better performance in terms of QoS than the standard allocation method by si...