Foundations of Health Service Psychology 2e presents a comprehensive science-based approach to clinical practice in psychology. The book systematically applies recent scientific advances in understanding human psychology to update the conceptual frameworks used for education, practice, and research in health service psychology. It includes significant elaboration on recent research, such as neural and behavioral science advancements in cognition, emotion, and behavior over the past decade. The role of evolutionary theory in comprehending human design is also emphasized, alongside substantial progress toward integrated primary care. The new edition has been reorganized to streamline its presentation. Key topics include a unified conceptual framework for health service psychology, an overview of the treatment process from intake through outcomes assessment, and major advances in both the science and practice of psychology. The discussion avoids highly technical language, making it accessible to students and practitioners across various fields.