Resistance, in psychoanalysis, refers to the client's defence mechanisms that emerge from unconscious content coming to fruition through process. Resistance is the repression of unconscious drives from integration into conscious awareness.
Sigmund Freud, the founder of psychoanalytic theory, developed his concept of resistance as he worked with patients who suddenly developed uncooperative behaviors during sessions of talk therapy. He reasoned that an individual that is suffering from a psychological affliction, which Freud believed to be derived from the presence of suppressed illicit or unwanted thoughts, may inadvertently attempt to impede any attempt to confront a subconsciously perceived threat. This would be for the purpose of inhibiting the revelation of any repressed information from within the unconscious mind.
Having developed the theory of resistance through his direct experiences with patients undergoing therapy, Sigmund Freud noticed that patients would avoid subjects and topics that struck too closely to uncomfortable memories or unacceptable emotions and desires. Freud then integrated these findings with his previous theories concerning the functions of the id, ego and super-ego. As a result, he eventually advanced his concept of resistance by developing it into a multitude of individual forms that included repression, transference, ego-resistance, "working-through", and self-sabotage.
The common theory behind many of Sigmund Freud's psychoanalytic techniques, alluding to the fundamentals of psychoanalysis as a science, was that it is possible that memories that have been lost from consciousness provide hints of their existence by the means of prompting certain thoughts and behaviors. Accordingly, the aim of psychoanalysis is to bring what is unconscious or preconscious into consciousness through verbalization. Afterwards, the act of bringing such thoughts into consciousness prevents them from motivating behavior and thus allowing the individual to exert more personal control.