Wide area monitoring, protection and control systems (WAMPACs) have been recognized as the most promising enabling technologies to meet challenges of modern electric power transmission systems, where reliability, economics, environmental and other social objectives must be balanced to optimize the grid assets and satisfy growing electrical demand. To this aim WAMPAC requires precise phasor and frequency information, which are acquired by deploying multiple time synchronized sensors, known as Phasor Measurement Units (PMUs), providing precise synchronized information about voltage and current phasors, frequency and rate-of-change-of-frequency. This book provides an overview of this emerging technology. Topics covered include an introduction to WAMPACs; reliability-based substation monitoring systems placement; system integrity protection scheme based on PMU technology; new methodologies for large scale power system dynamic analysis; a fuzzy-based knowledge discovery paradigm for on-line optimal power flow analysis; and false data injection attacks and countermeasures for wide area measurement system.