13easurement in sport and exercise psychology is a broad topic that includes measurement of psychological factors related to sport performance; of exercise adherence and related constructs; of team-related factors; of cognitive, affective, and self-assessment of athletes; and more (Tenenbaum, Eklund, & Kamata, 2012). There is not one "best" way to assess athletes and exercisers for performance enhancement, clinical concerns, or research purposes. Rather, the theoretical orientation of the practitioner and/or researcher guides the assessment and subsequent plan of action that is developed (see Chapter 2, this volume).The purpose of this chapter is to highlight key aspects of measurement in sport and exercise psychology. We begin with a brief history of measurement in sport and exercise psychology, followed by an overview of methods for capturing psychological processes in athletes. Next, we discuss cultural, ethical, and other issues related to measurement within sport and exercise psychology settings. We conclude M