Short-term psychodynamic therapy is recommended by NICE for treatment of depression, but it can also help with other disorders.
This is based on the idea that the past has an impact on your experiences and feelings in the present. This theory also suggests that important relationships, perhaps from your early childhood, set a pattern for how you relate to other people later in life.
The therapist usually aims to be as neutral as possible, giving little information about themselves. This makes it more likely that important relationships (past or present) will be reflected in the relationship between you and the therapist. This gives an important insight for you and the therapist to help you to work through your difficulties.
Developing a trusting and reliable relationship with your therapist is essential for this work, especially as the therapist may offer you long-term therapy.