© 2018 Dr Amanthi Thudugalage ; Wireless energy harvesting is one of the promising alternative methods to power next generation wireless networks such as wireless sensor networks and wireless communication networks. In Wireless Energy Transfer, in order to improve the energy harvesting capability, energy beamforming has recently drawn significant research attention, where we can direct the majority of transmit signal energy to a particular set of receivers. In this thesis, we consider energy harvesting in wireless networks and investigate optimum energy harvesting schemes with different objectives. This thesis is divided into two parts. In the first part, we focus on transmit energy beamforming for multi-user networks. We first obtain the optimum beamforming scheme in order to maximize the total energy harvested by all users. Next, we identify that total energy maximization can lead to big differences in the energy harvested by the users. Therefore, in the proceeding chapters we investigate different beamforming schemes to increase the fairness among the users. Furthermore, we extend our analysis to obtain transmit beamforming schemes to achieve throughput fairness among users. In the second part of this thesis, we focus on wireless energy transfer in point-to-point networks. In particular, we look at opportunistic energy transfer schemes to transfer energy from a power transmitter to a receiver when the receiver is imposed with a strict time deadline. We first formulate the problem for a general model to handle multi-antenna networks with different models for channel fading with the assumption that the energy consumed for channel estimation is negligible.We look at different special cases of the problem and compare the proposed solution to a non-causal solution as an upper bound. Then we reformulate the problem to consider the channel estimation energy and obtain the optimum opportunistic energy transfer scheme.