As the occupational therapy profession becomes increasingly evidence based, the valid and reliable evaluation of the client is critical to providing effective interventions. Employers, reimbursers, and evidence-based practice demand increased in competence in selecting, administering, and interpreting assessments. Authors reaffirm the importance of understanding the person as an occupational being and focus on how the occupational therapist's understanding of human occupation influences evaluation. Aligned with the Occupational Therapy Practice Framework, this updated text explores how to accurately evaluate the factors affecting occupational performance and explains essential aspects of evaluation, such as psychometric properties of standardized assessments, interpreting data that are applicable to practice, roles of culture and test bias, the importance of nonstandardized assessments to gain real-life knowledge, ethics, and using evaluation data to determine intervention effectiveness. Each chapter contains thoughtful questions to challenge readers and encourage learning, as well as case examples that promote real-world application.