Device-to-device (D2D) communications in conjunction with carrier aggregation. A base station (BS) may coordinate D2D communication between two wireless user equipment (UE) devices. A primary cell may be configured for communicating with each of the UEs. A secondary cell may be configured for D2D communication between the two UEs. The primary cell and the secondary cell may utilize different component carriers. Additionally, cross-carrier scheduling may be used, such that at least some control information for the secondary cell is communicated via the primary cell.