With the new advancements in distribution systems, such as the integration of renewable energy and bidirectional energy flow, it is necessary to equip power system engineers and students with better tools and understanding of how to study and analyze various phenomenon in distribution system. This book includes sections that address new advancements in distribution systems by discussing possible impacts associated with active distribution systems. It provides a foundational knowledge of the parts and equipment that make up a distribution grid, how they work, and how they are designed, maintained, and protected. The book highlights experimental modeling and analysis examples, which can be carried out by utilizing the software, PSCAD. It aims to introduce and familiarize the reader with how to use analytical tools and understand the engineering problems related to distribution system.