The book ‘Principles of Artificial Lift’ explains the basics and fundamentals as well as the recent technology advancements in the field of artificial lift of producing oil and gas wells. This book is written primarily for Production Engineers and Petroleum Engineering college students of senior level as well as graduate level. Although the purpose of this book is to help as well as teaching artificial lift, it is supposed to be useful as a reference book to the engineers, performing artificial application in Petroleum Industries. We recognize that the topic of ‘Principle of Artificial lift’ is not complete without a basic understanding of the concept regarding well-inflow performance and multiphase flow in pipes. This inflow performance is being elaborated in easiest manner at very beginning of the book. Regarding presentation, this book focuses on presenting and illustrating engineering principles used for designing and analyzing well bore lifting systems, rather than in depth Reservoir Engineering Theories. Since the material of this book is virtually boundless in depth, knowing what to omit was greatest difficulty with its editing. Many of the industry known basic formula are used instead of deriving the same.