Up until now, communications and radar sensing applications have employed different spectrum allocations and equipment, despite both employing the same physical phenomenon, i.e., the propagation of electromagnetic waves. Recently however, technological trends, like the usage of multiple antennas and wider bandwidths for communications, and the increased digitalization of radar processing, have made the integration of both systems easier. With this in mind, joint communications and sensing is likely to be one of the key features of 6G wireless systems, bringing about a plethora of new use cases. In this talk the promises and challenges of this new exciting technology will be discussed.