The TD-LTE market is picking up momentum, which likely will come at the expense of WiMAX. WiMAX and LTE share most of the RAN and core network, so the transition path from WiMAX to LTE will be smoother than, for instance, the transition path from HSPA to LTE, argued industry analyst Monica Paolini. However, there are a series of complicated decisions that have to be made during any such transition. Operators have to choose whether to overlay LTE on top of WIMAX or to simply swap the networks, and also have to consider whether they will use TDD or FDD spectrum. In all cases, however, WiMAX operators should start their assessment and planning processes now, to minimize possible future costs and challenges in moving to LTE. Commentary