This textbook provides a thorough presentation of the phenomena related to the transport of mass (with and without electric charge), momentum and energy.  It lays all the basic physical principles, and then for the more advanced readers, it offers an in-depth treatment with advanced mathematical derivations and ends with some useful applications of the models and equations in specific settings. The important idea behind the book is to unify all types of transport phenomena, describing them within a common framework in terms of cause and effect, respectively, represented by the driving force and the flux of the transported quantity. The approach and presentation are original in that the book starts with a general description of transport processes, providing the macroscopic balance relations of fluid dynamics and heat and mass transfer, before diving into the mathematical realm of continuum mechanics to derive the microscopic governing equations at the microscopic level. The book is a modular teaching tool and is used either for an introductory or for an advanced graduate course. The last six chapters are of interest to more advanced researchers who might be interested in applications in physics, mechanical engineering or biomedical engineering. In particular, this second edition of the book includes two chapters about electric migration, that is the transport of mass that takes place in a mixture under the action of electro-magnetic fields. Electric migration finds many applications in the modeling of energy storage devices, such as batteries and fuel cells. All chapters are complemented with solved exercises that are essential to complete the learning process.