Guillaume Dubois works at McKinsey & Company and serves clients in various types of industries. Guillaume graduated as an engineer from Ecole Centrale Paris, France. He started his career at Pratt & Whitney Canada, developing thermal models for airplane engines and at Enertime, developing financial models for biomass plants. He then joined PSA Peugeot Citroen, where he created and grow new modeling activities, teams and processes across R&D departments to improve energy efficiency of cars. He progressively held the different roles discussed in this book: modeling engineer - developing models, team manager - managing these engineers, project manager - being client of these teams. Guillaume authored La simulation numerique: Enjeux et bonnes pratiques pour l'industrie (Numerical simulation: Challenges and best practices for industry), published by Dunod, Malakoff, France, in 2016. Modeling and Simulation: Challenges and Best Practices for Industry is the English version.