A schema therapist practises schema therapy, an approach developed by Jeffrey Young specifically for people that standard cognitive behavioural therapy had not managed to help. The therapy works with schemas, deep patterns of belief and feeling formed early in life, often in childhood, that keep reasserting themselves in adulthood despite someone's best efforts to think their way past them.
Tracing the pattern back
Therapy begins by identifying these patterns as they show up in current life, then traces where they most likely originated, before moving to work on the emotional charge sitting behind them rather than stopping at the level of thinking alone. This emotional focus is part of what distinguishes it from standard CBT, which tends to concentrate more narrowly on thoughts and behaviours in the present.
Good evidence for entrenched difficulties
Schema therapy has good evidence for personality difficulties, particularly borderline personality disorder, and for chronic depression and anxiety that has not shifted with shorter approaches. It is, correspondingly, longer term than most talking therapies, often running for a year or more, reflecting how deeply rooted the patterns it addresses tend to be.