The Author began his professionnal carreer with an international oil company. Starting out with an interest in the Operation of Oil & Gas Facilities, his technical curiosity about their design made him move to engineering contractors to become expert in this area. As engineering manager of large turn-key projects, he gained the insight on engineering and amassed the knowledge presented in this work.Hervé Baron is a graduate engineer from IFP school and France's Ecole Polytechnique.