By God’s grace, this is the third book globally released in my 24 years of lecturing and engineering practice. The Scientists and Engineers design skill is now assessed by the ability to utilize developed software packages. Design is an art and should be taught from the fundamental principles. My earlier 2 books “Introduction to Principles of Chemical Processes" and "Modeling and Simulation of Reacting Systems and Environment” centered on understanding and the application of process principles and laws. This book is on teaching the fundamental of design. It is important for Students and Engineers/Scientists to appreciate parametric values obtained experimentally, or by modeling or from clients briefing and to thereafter develop innovative problem-solving design options. This book examines the various routes to design – experimental data, developed model equations, client’s specifications, etc. It is recommended for Students, Scientists and practicing Engineers.