Partial least squares (PLS) is a composite-based approach to structural equation modeling (SEM) that allows estimating complex interrelationships between constructs and their indicator variables. While PLS has gained much prominence in business research, management, and marketing applications of SEM, researchers in other areas of scientific inquiry, such as agriculture, engineering, environmental sciences and ecology, geography, medicine, and psychology, have also readily adopted the method. Building on an introduction of the fundamentals of measurement and structural theory, this chapter explains how to specify and estimate path models using PLS-SEM. Complementing the introduction of the PLS-SEM method and the description of how to evaluate analysis results, the chapter also offers an overview of complementary analytical techniques. A PLS-SEM application of the widely recognized corporate reputation model illustrates the method.