The electrical grids are, in general, amongst the most reliable systems worldwide. These large interconnected systems, however, are subject to a host of challenges - aging infrastructure, need for siting new generation near load centers, transmission expansion to meet growing demand, distributed resources, dynamic reactive compensation, congestion management, grid ownership vs. system operation and reliability coordination, etc. Some of the major challenges facing the electric industry today include balancing between resource adequacy, reliability, economics, environmental, and other public purpose objectives to optimize transmission and distribution resources to meet the growing demand. There are entities representing the concerns and it is a balancing act to meet today's consumer expectations in the changing society. Power system protection and control (P&C) is an important enabler to meet the challenges of the electrical grid in the 21st century. Evolutions in protection and restoration principles for interconnected power grids are made possible by the wide area measurement systems. Real-time adjustment of protection system's security-dependability is within reach given the advancements in technology and investments in communication systems infrastructures. Accurate modeling of large-scale interconnected power systems using ontology ' provides explicit and non-native explanations and definitions for common information being used amongst different groups in operation, planning, and protection. Likewise, improvements with processing relay settings, event recordings, distributed data sources, and impact of environmental and social issues and treaties can be achieved through information semantic or ontology. Advanced analysis, and operational tools, as well as, application of technologies such as Synchronized Phasor Measurement Units (PMU) are imperative to tackle complex and dynamic power system phenomena (stability detection, reactive power management, load encroachment, protection equipment failures, etc.) that will continue to affect grid reliability in the 21st century. This paper addresses applications of modem technology, advanced feedback control schemes using wide area measurements, and wide-area visualization techniques to improve grid reliability in complex and multifaceted power system conditions. Reliability aspects of P&C systems such as methods to identify and correct hidden failures and methodologies for optimal testing are also described. As new technologies offer significant improvements, large numbers of legacy P&C systems are still in operation. Upgrading aging P&C systems with modem counterparts not only reduces possibilities for failure, but offers unprecedented capabilities for reliable and high quality data and flexibility in operations which are presently largely untapped. Possibility to monitor equipment performance and to identify failed parts or components helps with equipment life projections and replacement decisions. Integration of P&C systems into Enterprise Systems for improved Asset Management, including value of standardization, is also assessed. The goal of this paper is to provide a comprehensive and systematic approach to meeting the P&C challenges of the 21 century.