A psychologist is a professional who practices psychology and studies mental states , perceptual, cognitive, emotional and social  processes and behavior. Their work often involves the experimentation, observation, and interpretation of how individuals relate to each other and to their environments.

Psychology is the scientific study of mind and behavior . Psychology includes the study of conscious and unconscious phenomena, including feelings and thoughts. It is an academic discipline of immense scope, crossing the boundaries between the natural and social sciences. Psychologists seek an understanding of the emergent properties of the brain, linking the discipline to neuroscience. As social scientists, psychologists aim to understand the behavior of individuals and groups.

A professional practitioner or researcher involved in the discipline is called a psychologist. Some psychologists can also be classified as behavioral or cognitive scientists. Some psychologists attempt to understand the role of mental functions in individual and social behavior. Others explore the physiological and neurobiological processes that underlie cognitive functions and behaviors.

Psychologists are involved in research on perception, cognition, attention, emotion, intelligence, subjective experiences, motivation, brain function, and personality. Psychologists' interests extend to interpersonal relationships, psychological resilience, family resilience,and other areas within social psychology. They also consider the unconscious mind.Research psychologists employ empirical methods to infer causal and correlational relationships between psychosocial variables . Some, but not all, clinical and counseling psychologists rely on symbolic interpretation.