In wireless sensor networks (WSNs), many sensor nodes which have limited energy sense the environment and relay their packets to the sink node by multi-hop routing. Thus, the nodes closest to the sink consume more energy than the other nodes and this ends up their lifetime early, which affect the overall network lifetime. Among several techniques of improving the performance of a WSN, the controlled mobility technique is commonly used for some of the network nodes and considered as one of the most important. In this thesis, different techniques of controlled mobility are introduced; controlled sink mobility, controlled nodes mobility and sink-node mobility techniques. Three controlled sink mobility algorithms; Distance Based Controlled Sink Mobility (DBCSM), Improved Distance Based Controlled Sink Mobility (IDBCSM) and Multi-Sink Distance Based Controlled Mobility (MSDBCM) algorithms are proposed to control the mobility of one sink or multiple sinks in the network. An algorithm for controlling the mobility of nodes called Energy Based Controlled Nodes Mobility (EBCNM) is also proposed. Finally, an algorithm for controlling the sink movement while the nodes are randomly moving through the network is proposed. The performance evaluation of different simulation scenarios is considered using NS2 simulator. The results show that the proposed algorithms improve the network lifetime and balance the energy consumption among the nodes. The network lifetime improvement in this work is about (19%-162%) over static network for sink mobility algorithms, about (31%-120%) over static network for nodes mobility algorithm and about (20%-38%) over static network for sink-node mobility algorithm. The average throughput is also improved by about (7%-146%) over static network for sink mobility algorithms, about (49%-160%) over static for nodes mobility algorithms and about (11%-62%) over static for sink-node mobility algorithm. The proposed controlled sink mobility algorithms decrease the average end-to-end delay by about (5%-12%) over static network. The results demonstrated a considerable improvement compared to previous schemes.