Resistance in psychotherapy broadly refers to a patient’s reluctance to change. At its core, resistance is the way in which a patient protects against the emotional pain or anxiety associated with change. The term resistance first appeared in Sigmund Freud’s writings on psychoanalysis and has since been adopted across psychotherapy approaches as a universal term to denote a patient’s difficulties in participating in treatment. This entry provides a brief description of resistance in psychotherapy and an overview of how resistance is understood in psychodynamic and cognitive behavioral approaches.