TABLE OF CONTENTS: Introduction, Con servation of Chemical Species, Foundations of Diffusion in MulticomponentMixtures, Mass Transfer in Binary Systems without Bulk Flow: Steady-State Examples, Mass Transfer in Binary Systems without Bulk Flow: Steady-State Examples, Mass Transfer in Binary Systems without Bulk Flow: Pseudosteady-State Examples, Mass Transfer in Binary Systems without Bulk Flow Unsteady-State Examples, Mass Transfer in Binary Systems with Bulk Flow, Mass Transfer in Multicomponent Mixtures, Approximate Solution of the Species Continuity Equation.