In previous chapters, behavioral modeling and digital predistortion (DPD) have been discussed for conventional wireless transmitters consisting of a one-branch single-input single-output (SISO) transmitter having a signal in one frequency band. Such transmitter architectures do not cope with the increasing demand for high data rates. Therefore, the newest wireless communication standards propose the use of more advanced transmitters architectures that take advantage of the space diversity in a multi-input multi-output (MIMO) system in order to increase the transmission data rate; or that offer a better use of the wireless spectrum by transmitting concurrently in multiple bands for different standards (concurrent multi-standard transmission) or for the same standards (carrier-aggregated transmission). In both cases, multiple paths are considered in the power amplification systems, where each path has its own nonlinear characteristics, which makes the modeling of the nonlinear behavior more complex. In addition, the interaction between the paths makes the increase in complexity exponential and the modeling efforts much harder. The present chapter will address the efforts made in modeling and linearizing these advanced transmitter topologies. First, MIMO transmitters' models will be investigated. Then, the concurrent multi-band transmission will be modeled and solutions for its linearization will be presented.